NO. 12«5. FA UNA OF MAMMOTH CA VE—HA Y. 225 



from the type locality and a few good ones were taken at the outlet of 

 Echo Kiver. In color they were a purplish gray. They were hiding 

 under flat rocks in the cold spring water. 



CRANGONYX VITREUS Cope. 



This species was observed in considerable numbers in Mannnoth 

 Cave, both in its type locality, Richardson's Spring, and in the Roar- 

 ing River district in small pools. When undisturbed it was most often 

 seen resting quietly or walking slowl}^ through the nmd on the bot- 

 tom with the bod}^ vertical and half buried in the soft ooze of the sur- 

 face. As a result of these movements there were innumerable trails 

 running in all directions, but never of a great length, as if the animal, 

 tiring of walking through the mud, had decided to swim to some more 

 renuuierative feeding ground. When once disturbed they swam rap- 

 idly about, either on their sides or with the back uppermost, or sought 

 safety l)y lying quietly behind some projecting pebble or mass of 

 earth. It was observed that when concealing themselves the}^ usually 

 lay on one side. Owing to their exceedingly smooth covering and 

 small size they were ver}^ difficult to catch. 



Suborder ISOPODA. 



Family ASELLID^E. 



MANCASELLUS MACRURUS Harger. 



This species was observed in two or three localities. A few speci- 

 mens were taken in a spring some 2 miles northeast of the hotel. They 

 seemed to be all very small and immature, but on careful examination 

 several of them could be seen carrying eggs. 



At the so-called mouths of Echo River, a series of three large 

 springs at the foot of the hill in which the entrance to Mammoth 

 Cave is found, If. iiiacrurm was collected in abundance. They were 

 of rather small size but decidedly larger than the specimens taken 

 from the spring mentioned above. 



They were usually found clinging to the under side of Hat rocks, 

 which lay in shallow water, and until a large number was disturbed 

 by turning over rocks I was not able to observe any of them crawling 

 al)out. They were living at this place in company with about equal 

 numbers of Aselhis styglas (Packard). The association seemed indis- 

 criminate, for I could not see that either species was partial to any 

 particular location or condition in the spring. 



C^CIDOTEA STYGIA Packard. 



This well-known species was taken in considerable numbers from a 

 small stream in one of the upper levels of Mammoth Cave and was 

 found in smaller numbers in small pools in other parts of the cavern. 

 Proc. N. M. vol. XXV— 02 15 



