124 KANSAS UNIVERSITY SCIENCE BULLETIN. 



the history of the majority of these caves goes further back 

 than that of the later Tertiary deposits, if so far. Such a small 

 amount of divergence as exists between the species peculiar to 

 the caves and their allies outside is proof that the former have 

 entered their subterranean dwellings at a comparatively recent 

 period." 



The following notes, giving a quite fair idea of the surround- 

 ings, are quoted from Miss Hoppin's letters, published by Gar- 

 man ('89) and by Faxon ('90) : 



"Wilson's cave is about fifty feet long, nearly as wide, oven- 

 shaped, and high enough to stand erect except around the sides, 

 The farmer had enlarged the entry to use the place as a cream- 

 ery. A small, very clear stream flowed along the left side, 

 having a width of two feet and a depth of three, with a tem- 

 perature of 54+ deg. F. About ten feet from the entrance, the 

 light struck the stream in such a manner that we could see 

 everything in the water without a lantern. The first things 

 that caught the eye were a lot of white crayfish, a dozen in all, 

 like those I took from the wells. It seemed as if I might take 

 every one of them. But, though blind, they have one or more 

 of the other senses very keenly developed. I am very sure they, 

 as well as the white fishes [Typhi ichthys subterraneus Gir.] , have 

 their tactile sense developed in an unusual degree. At the least 

 touch upon the water they dart away. As the net cautiously 

 follows, they escape adroitly, making no blunders as to the di- 

 rection of the approaching enemy, and hide in crevices of the 

 jutting rocks or in the muddy bottom of the stream. The mud 

 was easily stirred so that nothing could be seen. These crea- 

 tures, fish and crayfish, are only to be secured by patient wait- 

 ing and skilful management. The people at the cave say the 

 fish never bite, and cannot be taken with hook and line. The 

 crayfish were all found near the entrance, where there is con- 

 siderable light. Following the stream back to a dark recess, 

 reached by crawling on the slippery rocks, the light of the lan- 

 tern revealed a school of little, white fishes such as I secured 

 from the wells. All were very small. I saw half a dozen or 

 more, but secured only one. I concluded that the crayfish liked 

 the light. Perhaps they remain near the entrance because they 

 find there a supply of food. We found a few snails floating 

 about, but saw none in the dark pool where the fish were. 



