42 G 



PROCEEDTNGS OF THE NATIONAL MUSEUM. 



carpal se^iuent is produced and spinit'orni at its outer distal angle. 

 The nieros bears on its tip a slender s})ine almost as long as the 

 segment. 



The succ(H'ding pairs of walking legs are slender, hairy, and end in 

 very slender, acute, claw-like dactyls. 



The uropods are about one-half as long as the body. The 1)asal seg- 

 ment is slender, subcylindrical, straight or slig-htly curved, and the 

 terminal segnuMits are slender and gradually tapering from the base to 

 the end. The outer of these terminal segments is not much over half 

 as long as the inner. In a perfect specimen the inner is considerably 

 over half as long- as the l)asal segment. 



Length of body and uropods about '20 nnn. 



/A//>/V.v. Although I was able to learn comparatively little a])Out 

 the hal>its of this animal, the little 1 got is of interest and will serve 

 to contrast this species with its relatives. They w^ere found clinging 

 to the under side of fiat rocks well out in the cave stream, where the 

 current w^as strong and the depth usually over a foot. Their move- 

 ments were rapid, and they seemed to have no difficulty in running 

 from one place to another over the rocks, retreating always to the 

 lower side and hiding l)eneath some convenient angle. As a last resort 

 they would loosen their hold on the rock and float away in the water. 

 When in their native element, their sprawling legs and quick move- 

 ments wm-e very noticeable. When removed from the water they 

 were absolutely helpless, not even having strength sufficient to raise 

 their legs or straighten out their bodies. 



Compa7'i.^o7i and dhtrilmtion. — Cxcldotea 

 ii7chijacl-enf<!s Packard, from the same locality, 

 is described as follows:^ 



Body longer, narrower, and slenderer than in C. ^iygifi. 

 The antennte are sometimes very long and reach to the 

 end of the third joint of the second antenme; they are 

 sometimes nearly twice as long as in C. styg'ia, and are 

 purplish white, while th« fiagellum is provided with long 

 hairs. 



The second antenna' are as long as the head and extend 

 backward as far as the base of the abdomen. The legs 

 are much longer and slenderer than in C. stygia. The 

 abdomen is long and narrow, and the caudal appendages 

 are moderately long in one specimen and short in another. 

 In one individual the outer branch is much shorter and 

 smaller than in the others, and in most it is as long as 

 the basal joint. On the whole, the caudal appendages 

 are no longer than the telson or terminal segment of the 

 abdomen, while in C. stygia they are half as long as the 

 entire body. 



. This species forms in the antennae and slightly purplish 

 color and the proportions of the leg joints perhaps a 



I 



li^G. I.— C^CinOTEA 

 JACKENSI.S I'AfKA 



fiAnU'iinnle; 

 bCaudal -tyU'ts. Aft 

 ard. 



^ Packard, The Cave Fauna of North America, Mem. Nat. Acad. Sci., IV, 1887. 



