226 PROCEEDINGS OF THE NATIONAL MUSEUM. 



It was also found in abundance at the mouth of Echo River, where 

 it was livino- in conipan}' with 3L macrurus Harg-er. They were 

 usually found clinoino- to the stone walls of the pool in which they 

 were living- or could ])e seen slowly walking- over the bottom. When 

 disturbed their -movements were considei-u])ly (luickened, but they 

 were unable to move with any great rapidity. If when disturbed 

 they were clinging to the sides of their pool their first effort to 

 escape was by letting go and falling to the bottom; in case the pool 

 was deep this method was quite effectual. When removed from the 

 water they seemed almost absolutely helpless, the weak legs being 

 quite inadequate to the task of dragging along the heavy body. 



Suborder MACRURA. 



Family ATYID.E. 



PAL/EMONIAS GANTERI Hay. 



Tyjye.—^o. 27000, U.S.N.M. 



A most unexpected find in the Roaring River passage at Mammoth 

 Cave was a small eyeless shrimp, which proves to be a representative 

 of a family hitherto unrecorded from the North American continent. 



The discovery was made one morning when I had gone alone into 

 this passage with the intention of collecting as perfect a series as pos- 

 sible of the blind crayfish. A number of large C. j^ellucidus had been 

 secured, and I was endeavoring to find others of smaller size. To this 

 end the bottoms and the water of the clear pools were being examined 

 most carefully. While thus engaged, an ol)ject which seemed to be 

 a very small eyeless fish, appeared swimming slowly along near the 

 surface. From the way it moved in attempting to escape capture it 

 became evident that it could not be a fish, and a determined effort was 

 made to secure it. After a most exasperating chase, during which my 

 specimen seemed more than once to have eluded me, it was captured, 

 and I saw immediately that another animal had been added to the 

 fauna of the cave. 1 then set about finding others, and, knowing 

 what to look for, they were found quite easily. When first seen they 

 were usually resting quietly or were slowly walking on the bottom of 

 the pool, and were as insensible to the glare of my lantern as were the 

 crayfish. They were so transparent that several times they were 

 detected only by their shadows, and even when moving near the sur- 

 face they were almost invisible. When disturbed they at once left 

 the bottom, and by the rapid strokes of their subal)dominal append- 

 ages came to the surface, where they remained for some time before 

 sinking again to the bottom. All their movements were unmistakably 

 shrimp-like and very different from those of any of the other crusta- 

 ceans in the cave. They were very easily captured, either in the net 



