242 



CONNECTICUT GEOL. AND NAT. HIST. SURVEY. 



[Bull. 



1905. Cylisticus convexus, Richardson, Bull. U. S. Nat. 

 Mus., No. 54, p. 609. 



1905. Cylisticus convexus, Paulmier, Bull. N. Y. State Mus., 

 No. 91, p. 181. 



FIG. 78. Cylisticus convexus. 



Body oblong-ovate, a little more than twice as long as wide, 

 dorsal surface strongly convex; able to contract into a ball like 

 an armadillo. 



Head twice as broad as long with the antero-lateral angles 

 produced in large and rounded lobes ; median lobe small and 

 triangular and with acute apex. Eyes small and compound, 

 situated at the bases of the antero-lateral lobes. 



First pair of antennae inconspicuous, very small. Second 

 pair long and slender with flagellum composed of two sub- 

 equal joints; peduncular joints increasing in length distally. 



Thoracic segments subequal in length; large coxal plates not 

 distinct from their segments ; those of first segment expanded to 

 embrace the head, extending to base of antero-lateral lobes as well 

 as posteriorly in acute processes ; lateral margins straight. Legs 

 moderate, increasing in size posteriorly. 



Abdomen with six distinct segments not abruptly contracted; 

 first two with lateral margins covered by last thoracic segment; 

 third, fourth, and fifth with lateral lamellae prominent and curved 

 posteriorly to continue the even outline of the body. Telson tri- 

 angular, conically produced. Uropods considerably produced 

 beyond general outline of body, with peduncle extending a little 

 beyond the middle of apical process of telson ; inner ramus origi- 



