MEMOIES OF THE NATIONAL ACADEMY OF SCIENCES. 



85 



but a single species. The following table shows the distribution of the six species of true cave 

 spiders : 



Mammoth. 



WyaHdotte. 



Bradford. 



Carter. 



Weyer's. 



Anthrobia 

 niamniouthia 



Linyphia 

 subterranea 



? Nesticus carteri. 



Nesticus carteri. 

 Linyphia subterranea. 

 Linyphia incerta. 



Nesticus pallidus. 

 Linyphia weyeri. 

 Linyphia incerta. 



It will be seen that the two largest and consequently most ancient caverns, Mammoth and 

 Wyandotte, and in which the physical environment of the species is most unvarying, have but one 

 species each. The Anthrobia mammouthia is only found in Mammoth and the small caverns, i. e., 

 Diamond and Proctor's, situated about 5 miles from it. No other species occurred in these smaller 

 caves. The only spider found in Wyandotte Cave was the Linyphia subterranea, which also oc- 

 curred in the Carter caves, while in the Bradford Cave occurred a Nesticus, thought by Mr. Emer- 

 ton to be identical with Nesticus carteri. The Carter caves and Weyer's caves are small caverns, 

 all perhaps less than half a mile in length, with the exception of Bat Cave, which is perhaps over 

 a mile in length ; the distances are uncertain, these caverns winding about very irregularly, and 

 their length is only estimated by guess-work. 



It is iu the small caverns of Carter county, Kentucky, and the two Weyer caves (Weyer's 

 and the adjoining Cave of the Fountains) which are often but a few (less perhaps than a hundred) 

 feet below the surface, that the variation and number of species is greatest. In each set of caves 

 there are three species to one in Mammoth and Wyandotte caves. The individual variation was 

 the greatest in Nesticus pallidus, and, aslnight be suspected, in the eyes. The degree of variation 

 is indicated in Mr. Emerton's description. 



The spiders occurred more abundantly in all the caves than we expected. The individual 

 abundance was greater in the smaller caverns, especially the Weyer caves, than any others. In 

 the Mammoth Cave the Anthrobia occurred under stones in dry but not the driest places, on the 

 bottom at different points in the cave. Sometimes two or three cocoons would be found under a 

 stone as large as a man's head. 



The pedipalp Arthrogastra follow nearly the same law in distribution as the spiders. Pha- 

 langodes armata is restricted, like the genus Anthrobia, to Mammoth Cave and its neighboring 

 caves, while P. flavescens is a characteristic member of the Wyandotte fauna, a variety of it in- 

 habiting the Carter caves, and another Weyer's. 



As to the Myriopods, their distribution is very marked. Scoterpes copei is restricted to Mam- 

 moth Cave and neighboring grottoes, while Zygonopus whitei is confined to Weyer's and Luray 

 caverns. Pseudotremia cavemarum is the most widely diffused, inhabiting Wyandotte, Carter, and 

 Nickajack caves. 



Of the Crustacea, Cambarus pellucidus and Ccecidotcea stygia occur in the caves of Kentucky 

 and Indiana, while in Nickajack Cave they are replaced by different species. 



VI— LIST OF NORTH AMERICAN AND EUROPEAN CAVE ANIMALS. 



NORTH AMERICA. 



Vibrio 2 sp. 



Chilomonas emarginata Ehr. 



Chilodon eucullus Ehr. f 



Monas 2 sp. 



Colpodu f . 



Bodo f . 



Syuedra ulva. 



Nassula ? or Prorodon T . 



EUROPE. 



PEOTOZOA. 



Amoeba cellarum Joseph. Carniola. 

 Dendrocometea orcinus Joseph. Carniola. 

 Peridinium stygium Joseph. Carniola.* 



* In the spring, when vegetable and animal matter are borne in freshets into the caves, are found free-living 

 Infusoria. Sessile forms occur in the gills of the Proteus, at the mouth-opening and abdominal appendages of the 

 cave shrimps, and on the backs of the Isopods and Myriopods (Joseph). 



