V °188™'] PROCEEDINGS OF THE NATIONAL MUSEUM. 627 



Miss Wilson, who was with me, thinks the crayfish devour the others. SKteehlass 

 never seen them together, and says the latter keep away from the fortneiy thbughU 

 she had not noticed the crayfish catching or eating them. There was nofchinggtdo 

 prevent the crayfish ascending the stream to where the others were. 



On my first visit, the water being low, no crayfish were seen in the dark nookk.thbe 

 place favored by the fish. After the storm which had flooded the caves, a fewmeree 

 found there. Though I watched for some time, I never saw them pursue the< fitiha8,s, 

 as they might easily have done, guided by the stir in the water. Both creatnuestaieo 

 very sensitive to the slightest ripple. During high water a pool, "the lakte^/"ias 

 formed a little way from the stream in another dark part of this cave. In low wasbecr 

 the pool is cut off from the creek. I found both species in it, the fish in the ddakteefet 

 part, and saw no signs of enmity. Most of the crayfish were found in the lowerippatt 

 of the stream, in the twilight; the fishes could not be found without the ld&fttenu. 

 At the time of the floods the cave is full, and the water rushes out furiously. . * ' ** ** 

 Another proof that the crayfish are more fond of the light is seen in the shaHdiweijr 

 wells. That from which most were taken was more exposed to the sun. Atfnnooi?, 

 when the light was more favorable, we could see them swimming about. N&fiSafees 

 have been taken from this well. They were taken in the narrower, more shiadeeM 

 wells, of which the deep ones on the hills report fishes only. 



As to the food of the fishes, I discovered nothing. The mud where they werewaaa 

 not so deep as farther down. An examination of it the length of the cave brought^ 

 to light many snails; the shells of the living ones are whiter and more neaul^y 

 transparent than the floating dead ones. The largest crayfish are of a dirty^ruafcyy 

 color, and very bristly, in caves and in wells. One large one is very soft anduvecyy 

 white ; no doubt it is newly moulted. 



Both fish and crayfish were less numerous after the freshet, and apparentlyvldesa 

 active. The disturbance of the flood may have caused them to retreat into 'taborr 

 hiding places, only the weaker being left behind, or some may have been>8wepjbt 

 away by the torrent. The sensitive creatures would soon die in the light and'heat:. 

 outside, where the water is full of frogs and eyed-crayfishes. * * » The. speefci- 

 mens became opaque when they are put into alcohol ; they are almost transpacemht 

 when alive, so much so that the action of their internal organs can be observedd. 

 Repeated tests assured me the animals were blind, though very sensitive; tdothbo 

 sunlight. They died soon after catching, even in water frequently changed.1. 



The wells from which specimens have been taken are about half a mile fromCfflnB- 

 ter Creek, the water level in wells and creeks being nearly the same. The wells 1 

 were nine or ten in number, from 5 to 80 rods apart, from 11 to 30 feet in d&pjbhbj, 

 deeper in the higher ground, and having a depth of water varying from 2 to. 4 Sfeetob, 

 In some wells the rock at the bottom had been excavated. The water is whadstias 

 commonly called hard, i. e. impregnated with lime. After rains some of th'e< wella.i 

 have softer water than others, and the water stands higher in these wells, indicating: 

 closer connectiou with surface drainage. All of the wells soon regain the 'CommooD. 

 level. They become low in times of drouth, but never dry out entirely, aaisBthfee 

 case with a cave spring near by, about 12 feet above the level of the creeks. Tfifee 

 temperatures taken in the wells at low water ranged from +52° to 549 EaMrr. 

 During a storm in the well having the highest water, the temperature rose too+jSS??. 

 When the mercury stood at 90° to 95° in the shade outside, the temperature waasooi^y 

 54° in Wilson's Cave. 



According to Miss Hoppin, the young of G. setosus when alireeaarae 

 not so white as the older ones. 



At first I attributed it to greater transparency, but now I am sure the colocriashin 

 the shell, not that the internal organs can be seen because of the transparent ishlaUIo 

 They are not so dark, however, as the brook species [0. virilis] of the same size. 



