214 BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM 



(6) The fourth pleopod of the male (fig. 89, c) has the proximal 

 joint of the exopod five times as long as the distal ; the terminal setae 

 are longer than the distal joint. 



(7) The fifth pleopod of the male (fig. 89, d) is modified; it is con- 

 siderably elongated, rather longer than the sixth somite of the pleon, 

 stout and terminating in a single robust seta. 



Figure 89. — Acanthomysis dybowskii (Dershavin): a, Antennal scale and peduncle, X 24; 

 b, telson, X 24; c, fourth pleopod of male, X 24; d, fifth pleopod of male, X 24. 



This is a very distinct species, particularly in the broadly spatulate 

 form of the telson. Ii (1936b) referred specimens from the Korea 

 Straits with some doubt to this species. They showed two characters 

 not mentioned by Dershavin, a minute papilla on the eye, and the 

 presence of groups of long setae on the carpal and propodal joints 

 of the endopods of the third to the eighth thoracic limbs. In all the 



