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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That solum is the top layers of a soil profile [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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KarstBase a bibliography database in karst and cave science.

Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for shape (Keyword) returned 241 results for the whole karstbase:
Showing 1 to 15 of 241
The role of tributary mixing in chemical variations at a karst spring, Milandre, Switzerland, ,
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Perrin J. , Jeannin P. Y. , Cornaton F. ,
SummarySolute concentration variations during flood events were investigated in a karst aquifer of the Swiss Jura. Observations were made at the spring, and at the three main subterraneous tributaries feeding the spring. A simple transient flow and transport numerical model was able to reproduce chemographs and hydrographs observed at the spring, as a result of a mixing of the concentration and discharge of the respective tributaries. Sensitivity analysis carried out with the model showed that it is possible to produce chemical variations at the spring even if all tributaries have constant (but different for each of them) solute concentrations. This process is called tributary mixing. The good match between observed and modelled curves indicate that, in the phreatic zone, tributary mixing is probably an important process that shapes spring chemographs. Chemical reactions and other mixing components (e.g. from low permeability volumes) have a limited influence.Dissolution-related (calcium, bicarbonate, specific conductance) and pollution-related parameters (nitrate, chloride, potassium) displayed slightly different behaviours: during moderate flood events, the former showed limited variations compared to the latter. During large flood events, both presented chemographs with significant changes. No significant event water participates in moderate flood events and tributary mixing will be the major process shaping chemographs. Variations are greater for parameters with higher spatial variability (e.g. pollution-related). Whereas for large flood events, the contribution of event water becomes significant and influences the chemographs of all the parameters. As a result, spring water vulnerability to an accidental pollution is low during moderate flood events and under base flow conditions. It strongly increases during large flood events, because event water contributes to the spring discharge

Observations on Caves, Particularly Those Of South Australia - 1862 , 1962,
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Lane, Edward A.

The historical study of Australian caves and caving areas is fascinating although involving the expenditure of vast amounts of time. Australia's early days are unusually well-documented, but in the case of caves the early history is usually wrapped up in rumour, hearsay and clouded by lack of written record. Most research work means long hours poring over old newspaper files, mine reports, land department records and so on, little of which is catalogued. A small number of exploration journals and scientific studies have extensive material on special cave areas, and of these, the volume by Rev. Julian Edmund Woods, F.G.S., F.R.S.V., F.P.S., etc., and is one of the most interesting. This book gives the ideas and beliefs of 100 years ago concerning the origin, development and bone contents of caves and makes interesting reading in the light of more recent studies of cave origins. Wood's study "Geological Observations in South Australia : Principally in the District South-East of Adelaide" was published in 1862 by Longman, Green, Roberts and Green, London. In a preface dated November 15, 1861, Rev. Woods points out that the book was written while he was serving as a missionary in a 22,000 square mile district, and "without the benefit of reference, museum, library, or scientific men closer than England". Up to the time of writing, almost no scientific or geological work had been done in South Australia and much of the area was completely unexplored. The book, also, contained the first detailed description of caves in the south-east of the state. Father Woods writes about many different types of caves in South Australia, for instance, the "native wells" in the Mt. Gambier/Mt. Shanck area. These are caves, rounded like pipes, and generally leading to water level. Woods points out their likeness to artificial wells. He also writes of sea cliff caves, particularly in the Guichen Bay area, and blow holes caused by the action of the waves on the limestone cliffs. Woods discusses many other types of caves found further inland, particularly bone caves. Father Woods discusses cave origins under two sub-heads: 1. Trap rock caves generally resulting from violent igneous action, and 2. Limestone caves resulting from infiltration of some kind. He is mainly concerned with limestone caves which he sub-divides into (a) crevice caves - caves which have arisen from fissures in the rock and are therefore wedge-shaped crevices, widest at the opening, (b) sea-beach caves, caves which face the seashore and are merely holes that have been worn by the dashing of the sea on the face of the cliff, (c) egress caves, or passages to give egress to subterranean streams, (d) ingress caves, or passages caused by water flowing into the holes of rocks and disappearing underground. These caves would have entrance holes in the ground, opening very wide underneath, and having the appearance of water having entered from above, (e) finally a group of caves which he lists by use as "dens of animals".

Detection of caves by gravimetry., 1964,
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Chico Raymundo J.
For gravimetric investigations, a naturally occurring limestone cave may be compared with a buried empty sphere or cylinder, depending on its shape. The practical limit of detection for a subsurface void, utilizing available equipment (Worden gravity meter) and standard field procedure, is 0.1 milligal. Most corrections normally required by the gravimetric method may be neglected in cave detection, but the altitude control for the field traverse must have an accuracy of 0.1 foot. The detectability of a limestone cave, based on field work done at Luray Caverns, Virginia, and at other localities, is related to its shape, Radius (R), and distance from surface to the cave center (Z). It follows a non-linear relationship. Detectability is possible only when R3/Z2 = 4.3 feet and R3/Z = 2.89 feet. For a cave room and a cave passage respectively.

Laboratory and field evidence for a vadose origin of foibe (domepits)., 1965,
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Reams Max W.
Foiba (plural, foibe) is a term derived from the northeastern Italian karst region. The word is here suggested for use in preference to other terms referring to vertical cavities in soluble rocks. Foiba is defined as a cavity in relatively soluble rock which is natural, solutional, tends toward a cylindrical shape, and possesses walls which normally approach verticality. In laboratory experiments, limestone blocks were treated with dilute hydrochloric acid, and cavities resembling foibe were produced. Vertical walls developed only when a less soluble layer capped the limestone block or when the acid source was stationary, allowing acid to drip to the area directly below. Water analyses from foibe in central Kentucky and Missouri indicate that the water has had less residence time in the zone of aeration than other waters percolating through the rocks and entering the caves. In central Kentucky, foibe seem to be developed by migrating underground waterfalls held up by less soluble layers or by water moving directly down joints below less soluble layers. In Missouri, foibe are formed by joint enlargement below chert layers. Those foibe in the ceilings of caves are complicated by the enlargement of the lower part of the joints by cave streams during fluctuating water table conditions. In limestone caves of Kansas, foibe are formed in a similar manner as in Missouri. The foibe of the gypsum caves of Kansas are formed mainly on the sides of steep collapse sinkholes and lack joint control although they form beneath less soluble layers in the gypsum. Dripping water is necessary for the development of vertical walls by solution. Less soluble layers seem to be the unique feature which allows water to drip and pour into foibe. The floors of foibe are formed by less soluble layers or near the water table. If foibe intersect previously formed cave passages, no floors may develop.

Contribution on the study of European Bathynella: Bathynella natans Vejdovsky, a dilemma to resolve., 1966,
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Serban Eugne.
After a minute study of the structure of the 8th male pereiopod in some Bathynella populations from Romania and England, the structure differences which were found allowed to identify two well individualized kinds of pereiopods; they were named type natans and type stammen. Taking into account the striking differences between these two types, B. stammeri (Jakobi), which since 1954 is considered to be a subspecies of the natans species, was separated out of the species B. natans sensu Jakobi (1954). The populations understudied were collected in England and Romania, their minute study being the object of an other note, collaboration with T. Gledhill. The facts led to the conclusion that Jakobis opinion (1954), which dominated the taxonomy of this group, doesnt entirely correspond to the reality, the two taxonomical units being characterized as follows:; Bathynelta natans Vejdovsky, characterized by the 8th male pereiopod (fig. I A) with a triangular, well developed anterior plate (fig. 3 A-D-a; 7 A-D), of the same length with the exopodit, a cylindrical internal lobe (fig. 3 A-D-b,) and a little lobe (fig. 3 A-D-c) of a reduced size;; Bathynella stammeri (Jakobi) differing from the first with respect to the anterior pinte (fig. 2 A-D-a; 6A-C) which is rectangular in shape and has a prolongation in the distal outer angle, to the conelike internal lobe (fig. 2 AD-b), and to the little lobe (fig. 2 A-D-d) which is twolobed in this case. After discussion on the relationship between B. catena Vejd. and B. stammeri (Jakobi) it is shown that differences observed in the 8th male pereiopod structure give important indications about the above species to the effect that they are not very closely related. If one takes into account also their wide spreading area, and the individualisation of some populations due to important, characteristic traits; we are obliged to classify them into two different sub-genera. In the first one, the species catena is included; which will keep by this way the very name of the genus, and in the second, termed here Antrobathynella, the species stammeri. In conclusion, what was till now considered as Bathynella natans Vejdovsky sensu Jakobi, was divided into two distinct species each of them pertaining to two different sub-genera, that is: Bathynella (Bathynella) natans Vejdovsky and Bathynella (Antrobathynella) stammeri (Jakobi). It is demonstrated that the synonymy Jakobi made between B.chappuisi and B. natans is perfectly true under the new conditions too, because it was Delachaux (1919) who rediscovered B.natans Vejd., not Chappuis (1914). The material found by Chappuis in Basel (1914) appears to pertain to B. stammeri (Jakobi) differing both from the individuals from the Grotte de Ver (Delachaux, 1919) and from Prague (Vejdovsky, 1882).

Underground solution canyons in the Central Kentucky karst, U.S.A., 1967,
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Watson Richard A.
Solution canyons are underground voids 1 to 15 + meters wide, 3 to 45 + meters high, and 30 to 300 + meters long. Floors are stepped, ceilings level. Size increases downstream. Their course is sinuous, with some angularity. They occur parallel to and directly under or slightly offset from the thalwegs of re-entrant valleys tributary to major karst valleys. A section across a re-entrant and underlying solution canyon shows a rough hour-glass shape. Solution canyons are related genetically to solutional vertical shafts, forming where removal of the impermeable sandstone caprock permits the vertical descent of water through jointed limestone. Surface runoff concentrates along re-entrant thalwegs where a largo quantity of water goes underground. This water, plus subsurface water flowing over the caprock breached by the valleys, follows the easiest route to baselevel down major vertical joints oriented parallel to the thalwegs. Solution by water seeping down these joint planes forms solution canyons.

Caves of Vakuta, Trobriand Islands, Papua, 1969,
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Ollier C. D. , Holdsworth D. K

In a previous paper (1968a) we described caves of Kiriwina, the largest of the Trobriand Islands, a group of coral islands situated 100 miles off the north-east coast of Papua. This paper records caves of Vakuta, a smaller island south of Kiriwina. Vakuta is shaped like a boomerang (Figure 1) and is separated from the southern tip of Kiriwina by Kasilamaka Passage, about half a mile wide. The area of Vakuta Island is approximately 11 square miles. The island contains three villages, the most important being Vakuta Village which has a Methodist (now United Church) Mission. A track links Vakuta Village to Kasilamaka Passage which can be crossed by native canoe; the track continues on Kiriwina to Losuia, 40 miles north. Vakuta Island has a population of about 500. The Vakutans are of the same mixed Melanesian-Polynesian stock as the people of Kiriwina. Woodcarving is not practised to the same extent as in Kiriwina and the quality is generally low. However, some canoes have particularly well decorated prows. The influence of the Mission is very evident in the dress of the Vakutans and in the village, old cast-off clothing, often quite dirty, is the rule. In the fields the women wear grass and fibre skirts though the men were not seen to wear a pubic leaf as usual in Kiriwina, but shorts. Papuan Airlines operate a weekly flight between Port Moresby and Losuia, the Administration Centre, using Skyvan aircraft. Weekend tourist charter flights in DC-3 aircraft arrive frequently, but irregularly, from Port Moresby and occasionally from Lae and Rabual. The authors visited Vakuta Island in December, 1968. Guides were recruited locally and we were fortunate to be assisted by Mr. Gilbert Heers, the only European resident of the island, who speaks fluent Kiriwini which made communication with our guides relatively easy. With his help, we were able to obtain accounts of the legends and traditions associated with the caves on the island. We have also had valuable discussions about Vakuta and the customs and legends of the Trobriand Islands with Mr. Lepani Watson, M.H.A., who was born on Vakuta, and Mr. John Kasaipwalova, a Trobriand Islander now studying at the University of Queensland. We are most grateful for the assistance of these people. Although the most accurate map of the Trobriands is an Admiralty chart, the authors used an old U.S. Army map which was based on a pre-war Government survey. The caves were roughly surveyed using 100 ft tape, prismatic compass and abney level. The village rest-house became the social centre of the village during our stay. We had no difficulty in finding food. A surprising variety of foods such as yams, sweet potato, eggs, pineapples, soursop, tomatoes and fresh coconut appeared and payment was accepted eagerly in stick tobacco and newspaper. Payment in cash was rarely appreciated, though it will become more useful now that a trade store has been established by the Village Co-operative. To avoid repetitive explanations of features in the accounts of individual caves, various general topics will be discussed first.

Size and growth of the eyes of the troglobitic Salamander Typhlotriton spelaeus., 1974,
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Besharse Joseph C. , Brandon Ronald A.
The eyes of larval T. spelaeus grow by negative allometry, but in allometric coefftcients they are not greatly different from E. lucifuga. The major differences in eye size, both absolute and relative to body size, between T~ spelaeus and E. lucifuga are established prior Io the larval growth period. The eyes of T. spelaeus cease to grow at metamorphosis and are reduced in size thereafter. In addition, there is increased individual variability and bilateral asymmetry of eye size in adult T spelaeus compared to both adulI E lucifuga and larval T. spelaeus. This variability, expressed as relative dispersion about mean eye size, is significantly greater than in E luci.fuga, and appears to result from three factors: 1) postmetamorphic cessation of eye growth, 2) wide variation in body size and eye size al metamorphosis, and 3) postmetamorphic shape changes and reduction of eye size.

Karst processes of the eastern upper Galilee, Northern Israel, 1974,
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Gerson R,
Karst processes dominate most of the geomorphic activity in the Upper Galilee, consisting mainly of dolomites and limestones. Study of the chemical evolution of water passing through the karst hydrologic cycle clearly shows that the major portion of its carbonate solute is gained subaerially and in the upper part of the vadose zone. Most cave and spring water is already saturated with respect to aragonite and calcite.The karst depressions typical to surface morphology are mostly associated with fault-line traces. Their evolution is possible mainly in areas sloping initially less that 5[deg].The absence of evolved caves, representing well-developed karst of an earlier period, is attributed mainly to the marginal climate throughout the past combined with tectonic, and hence hydrologic, instability of the region.The discharge of the karst prings shows clearly dependence on annual precipitation, with a lag of about 2 years of the response to drought or more humid periods. Long-term fluctuations are larger in the smaller T'eo Spring than in the affluent 'Enan Springs.Most of the denuded material is extracted from the region as dissolved load via underground conduits and only small amounts as clastics. Mean long-term denudation is approximately 20 mm/1000 years, averaged for the surface area contributing to the springs.In spite of the above, most topographic forms are shaped by runoff erosion, active during medium to high intensity rainstorms. Solution processes prevail during low to medium rainfall intensities, while different parts of the region are denuded at similar rates. Even in karst depressions, erosion becomes dominant after their bottoms are covered by almost impervious terra-rossa mantle

Geomorphology of the North Karst, South Nahanni River Region, Northwest Territories, Canada, PhD Thesis, 1976,
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Brook, George Albert,

First investigated on the ground in June 1972, the Nahanni karst of northern Canada is the most complex karst terrain yet reported from high latitudes. It is centered at 61°28' N, longitude 124°05' W and lies within the zone of discontinuous permafrost. Mean annual temperature is 24°F and mean total precipitation 22.3 inches. Principal karst forms are fracture-located karst streets and irregularly-shaped closed depression called karst platea which may be up to 600 feet in depth. Platea often contain karst towers which are residuals of wall recession. Vertical-walled pond dolines up to 120 feet deep are common in bare karst areas while subjacent karst collapse, subsidence and suffosion depressions occur on marginal shale- and drift-mantled surfaces. Three small poljes have been identified, two produced entirely by solution, the other a structural form. These are periodically inundated. There are several peripheral fluvial canyons up to 3,000 feet deep that are blocked by glacial drift and which presently drain underground. Similarity in the hydrogeological properties of Nahanni Formation limestones at a variety of scales has led to the development of morphologically-identical karst forms which range in size from inches up to hundreds of feet. Furthermore, many of these landforms are part of a developmental sequence that at one scale links vertical-walled dolines, karst streets, platea and poljes; and at another links solution pits, grikes and joint hollows on limestone pavements. The evidence suggests that poljes form by the coalescence of dolines and uvalas just as Cvijic suggested in 1918. In attempting to explain the almost "tropical" nature of the sub-arctic Nahanni karst landform assemblage, a number of facts are of importance.
(a) The Nahanni Formation limestones have been highly warped and intensively fractures during the past one million years. Open fractures have encouraged karstification by allowing easy movement of water underground. Warping has provided the relief necessary for the development of solutional forms with a distinct vertical component.
(b) The karst can not be considered relict because it was glaciated during the Pleistocene. In addition the hydrological activity in it today is comparable with that in many humid tropical karst areas.
(c) Solutional denudation rates governed by aspects of surficial and bedrock geology may in some localized areas be equivalent to rates in humid tropical carbonate regions.
(d) At present rates, the most highly developed forms could have been produced within the last 200,000 years and because there is evidence to indicate that the karst may not have been glaciated for up to 250,000 years, such a period has been available for solutional development.
Because the Nahanni region has not been glaciated for an extremely long period, it may be one of only a few high-latitude carbonate terrains that have had time to develop fully. Its very existence questions the validity of the concept that the intensity and direction of karst development is climate-controlled. In the Nahanni at least, the structural and lithological properties of the host limestone appear to have been of greater importance. The labyrinth karst type present in regions of humid-tropical to sub-arctic climate, is an outstanding example of a structurally-controlled karst landscape. It may well be that the same controls also influence the distributions of other karst types.

Frustration and New Year Caves and Their Neighbourhood, Cooleman Plain, N.S.W., 1977,
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Rieder L. G. , Jennings J. N. , Francis G.

Frustration and New Year Caves are active between-caves, paralleling in plan and profile the ephemeral stream bed of the V-shaped valley in which their entrances are found. The main streamsink in this valley system feeds their stream, which in turn supplies Zed Cave, a short outflow cave just outside the mouth of this valley. This modest derangement of surface drainage pattern is in keeping with the caves which show slight vadose modification of epiphreatic cave development. Although these active caves are young, they probably formed prior to a Late Pleistocene cold period (30,000 to 10,000 BP) on the basis of soils evidence. Clown Cave on the brow of the valley, a dry cave with indications of sluggish phreatic development, is related to a planation phase of Middle or Lower Tertiary age before valley incision. Bow and Keyslot Caves are abandoned in and out and outflow caves respectively, formed when the surface stream channel was a few metres above the present valley bottom so they antedate the active river caves a little. This hydrologically independent part of the Cooleman Plain mirrors in most respects the major parts draining to the Blue Waterholes, differing chiefly in the greater proportion of between-caves discovered so far.

The fine structure of Hamann's organ in Leptodirus hohenwarti, a highly specialised cave bathysciinae (Coleoptera, Catopidae)., 1978,
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Accordi Fiorenza, Sbordoni Valerio
Hamann's organ in Leptodirus hohenwarti a highly specialized cave Bathysciinae, has been studied under the TEM, SEM and light microscope. This receptor organ located in the 7th, 9th and 10th antennal articles and previously referred to as the "vesicule olfactive" and as the "antennal organ" or "antennal vesicle", reaches its highest degree of structural complexity in leptodirus. This paper attempts to establish some degree of synonymy among the terms used by earlier authors in describing the various antennal parts and sensilla. Five types of sensilla to be found in the organ are described, namely cribrose-stick sensilla, cribrose-utricular sensilla, star-shaped sensilla, claviform sensilla and branching setae. Comparisons within Bathysciinae species and among the latter and other subfamilies of Catopidae reveal differences in the number of vesicles and in the number and structures of sensilla, these differences appear to depend on i) the degree of phylogenetic relationships among taxa and 2) the degree of specialization to cave environment. The considerable complexity of Hamann's organ, unrivalled by other insects organs, apart from light receptors, suggests that it has a plurality of functions. Its hygroreceptor role, supported by recent experimental work, is discussed here.

A critical review of hypotheses on the origin of vermiculations., 1978,
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Bini Alfredo, Gori M. Cavalli, Gori Silvio
Mud and clay vermiculations are irregular and discontinuous deposits of incoherent materials, almost ubiquitous, found both inside and outside of caves, overlying limestone or other materials, they are formed from many substances (clay, mud, candle-black, colloidal silica, etc.) also their shape dimensions vary greatly. The following genetical hypotheses have been proposed: fossil fillings; chemico-genetical deposition; biological formation; mechanical deposition from moving water or air; clay-layer drying process (Montoriol-Pous hypothesis); physicochemical deposition from drying liquid films. The last is proposed by the authors who, having discussed the various hypotheses, give many examples and the results of some experiments. They distinguish two types of vermiculations: Type 1 or negative vermiculations Type II or normal vermiculations. The genesis of type I is explained by the Montoriol-Pous hypothesis; these vermiculations are large and made of clay or other colloidal material, and are due to the gradual drying of a layer of clay or other substance. The last stage of this drying process causes the vermiculations to form in a more or less dried state. The vermiculations of the second type are small and thin, much ramified and always with a clear halo around them. Vermiculations consisting of many materials have been observed, usually as macroscopic aggregates. They are caused by the drying of a liquid film containing suspended colloidal particles. The proposed mechanism provides a good explanation of all the observed characteristics of vermiculations.

The sensoral outfit of subterranean Trechinae. II. Ultrastructure of the Elytral trichobothria., 1978,
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Juberthie Christian, Piquemal Francoise
The ultrastructure of trichobothria (Tm2, Tr2, Tr4) of the elytra has been studied in the troglobitic Coleoptera Geotrechus vulcanus and Aphaenops cerberus. Two bipolar neurons innervate these trichobothria. The first ends at the level of the hair base, and its distal segment contains a tubular body, characteristic of mechanoreceptive bristles. The other does not possess a tubular body, and its distal segment ends in the bristle canal; its function is unknown. The trichobothria possess one glial enveloping cell, one trichogen cell, and one tormogen cell; the latter two show an apical, common, large, receptor lymph cavity. The small trichobothria are innervated by a large mechanoreceptor neuron, and by 4 smaller neurons; its function is unknown. The trichobothria of blind Trechinae are highly specialized. A cuticular cup enshrines the hair base; hair and cup move together. The large amplitude swaying movements of the hair are controlled by a spongious tissue around the cup. The trichobothri of Trechinae and Periplaneta have the same type of cuticular dome-shaped structure, and differ from trichobothria that arise from a cavity in the cuticle.

A new Microparasellid from subterranean phreatic waters of Italy: Microcharon arganoi n. sp. (Crustacea: Isopoda)., 1978,
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Pesce Giuseppe L. , Tete Pierantonio
Microcharon arganoi, a new Microparasellid from subterranean waters of Southern Italy is described. For the shape and ornamentation of pleopod II of females and for the morphology of pleopod II of males, the new species is clearly related to the phyletic line which includes all the Western and French species of the genus. However, from all these species and from all the other ones M. arganoi differs by the ornamentation of the antennae, maxillipeds and pereiopeds, by the shape and ornamentation of pleopods I and II of males and II of females. and by ratio endopod/exopod of pleopod III. The new species is the first one from the subterranean freshwaters of Italy.

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