NEW CRAYFISHES FROM FLORIDA — HOBBS 



391 



Antennules of usual form; a spine present on ventral side of basal 

 segment. 



Antennae extending caudad slightly beyond tip of telson. 



Antenna! scale broad; extends cephalad to tip of rostrum; not as 

 long as peduncle of antennae. Broadest anterior to middle. Spine 

 on outer margin weak. 



First pereiopod long and slender; palm subovate, entirely tubercu- 

 late. Fingers with weak median dorsal ridge and bent decidedly 



Figure 15. — Cambarus acherontis Lonnberg: a, Mesial view of first pleopod of male, form I; 

 b, cephalic view of first pleopod of male, form I; c, caudal view of first pleopod of male, 

 form II; d, caudal view of first pleopod of male, form I; e, lateral view of first pleopod of 

 male, form I;/, mesial view of first pleopod of male, form II; g, ischiopodites of third and 

 fourth pereiopods of male, form I; h, epistome of male, form I; j, annulus ventralis; /, 

 antennal scale; k, lateral view of first pleopod of male, form II. Pubescence has been 

 removed from all first pleopods. 



ventrad. About 11 tubercles in silhouette irregularly arranged along 

 inner margin of palm. 



Movable finger with about 19 tubercles along mesial margin; lateral 

 margin with one corneous tubercle in proxunal third and about five 



