268 FRANK H. PIKE. 



THE GROSS ANATOMY. 



General External Appearance. Like the cave crustaceans of 

 southern Indiana and Kentucky, the Cuban shrimp is clear white 

 or colorless. The antennae are extremely long and the chelae 

 are relatively longer than in the out-door or normal species. The 

 eye-stalks are plainly visible but not as prominent as in the nor- 

 mal species. In the cave-crayfish from southern Indiana and 

 Kentucky the eye-stalks are almost hidden beneath the rostrum, 

 when viewed from above. They are much more prominent in 

 the present species. 



Surface Views of the Eye-stalks. I. Viewed from the side, 

 with moderate magnification, the eye-stalks are seen projecting 

 forward from the anterior lateral part of the head just below and 

 to one side of the rostrum (Fig. i). The eye-stalk is not termi- 



FIG. I. Eye-stalk viewed from side, r, rostrum; <?, eye-stalk; a, optic gang- 

 lion ; /', optic nerve ; c, retina ; d, space filled with haemolymph. 



nated by a hemispherical cap as in the normal species, but by a 

 peculiarly shaped, somewhat acute-tipped cone. The stalk is 

 directed upward, forming a small angle with the horizontal. If 

 the line drawn from the middle point of the base through the tip 

 be taken as the long axis of the eye, the part of the stalk above 

 this line will be at all points convex in outline. Beginning at 



