THE DAJID;E 399 



Hoek lias stated that the male in this stage is com- 

 pressed laterally, so as to look like an Amphipod, and that 

 it is fixed to the body of the female by the aid of a sucker. 

 Giard and Bonnier remark that the lateral compression 

 would be very astonishing, since all the Epicarids in the 

 cryptoniscian stage tend to be flattened. From specimens 

 sent me by Dr. Fulton of the Scotch Fishery Board, I 

 should say that these cryptoniscian forms of the male were 

 decidedly flattened, not compressed, but these specimens 

 were taken or found apart from females, whereas Dr. 

 Hoek's may have been modified by their position as 

 attached to the female. The suboral circular sucker is a 

 conspicuous object, which attracted Dr. Fulton's attention 

 at once. It appears to have escaped notice that this ring 

 is shown in the figure of Dajus mysidis, Kroyer, on plate 

 28, fig. IA, of the ' Voyages en Scandinavie, &c.' Dr. 

 Hoek has figured the curious hand-shaped spines on the 

 sixth joint of the legs. Some of these spines are split as 

 it were into five finders and a thumb. 



o 



Three species are at present allotted to the genus : 



Dajus inysidis, Kroyer, 1846, on Mi/sis oculata 

 (Fabricius). 



Dajus mixtus, Giard and Bonnier, 1889, on Mysis mixta, 

 Lilljeborg. 



Dajus siriellce, Sars, 1885, on SirieUa Tfiompsonii 

 (Milne-Edwards). 



Aspidopliryxus, Sars, 1882. The animals are attached 

 to the back of the perason of the host. The female is 

 much more curved than in Dajus. It has the five pairs 

 of feet more elongate, the first four pairs of marsupial 

 plates very small, not overlapping from side to side, the 

 last pair very elongate, soldered together longitudinally ; 

 the pleon unsegmented, without appendages. In the male 

 the pleon has an indication of the segments of which it is 

 composed, the sixth especially being distinct ; the only 

 appendages are the two-jointed uropods. 



AspidopJiryxus peltatus, Sars, 1882, on Enjtlirops ery- 

 tlirophilialmus (Goes). Eggs many and small. 



Aspidoplvryxus Sarsi, Giard and Bonnier, 1889, on 



