22 



The spines of the carapace, in addition to a small tooth at the orbital angle, 

 are a post-orbital, an antenna!, an hepatic, and a branchiostegal, the last being 

 more an acute lobule than a spine. 



The abdominal terga are sharply carinated from the anterior end of the 

 :3rd to the posterior end of the 6th. The 6th abdominal somite is between a 

 half and a third again as long as the 5th. The telson is longer than the endo- 

 podite, longer even than the exopodite, of the caudal swimmeret and is 

 trifurcate. 



Eyes rather large. Antennular flagella as long as the carapace plus half 

 the rostrum, measured in the mid-dorsal line, foliaceous in the greater part of 

 their extent, but gradually tapering to a filament. As in the previous species 

 the flagella are lightly channelled and the inner is twisted at base so as to 

 ensheathe the outer. 



In the unique specimen the carapace and rostrum are 26 millim. long, and 

 the abdomen is 40 millim. 



Colour in life, red. 



From the Andaman Sea, off the South island, 405 fathoms. 



Regd. No. ~ (Type of the species). 



HALiroRUS, Spence Bate. 



Ealyporus, Spence Bate, Aim. Hag. Nat. Hist., Sept. 1881, and Challenger Crustacea Hacrura, p. 281. 

 Hymenopeneus, S. I. Smith, Proc. U. S. Nat. Mns., 1885, p. 179. 



Differs from Peneus in the following characters : — 



The carapace is usually, but not always, submembranous, and is always 

 armed with at least four teeth on either side, namely, a supra-orbital, an 

 antennal, a true branchiostegal, and a hepatic. (The rostrum is toothed dorsally 

 only, as in all the subgenera of Peneus excepting Pencil* itself). 



The antennular flagella, one or both, are very long. The eyestalk has a 

 small tubercle on its inner face. 



The mandibular palp (endopodite) has the first joint long broad and ovate, 

 and the second joint long (though shorter than the first) slender and pointed. 



The exopodite of the 2nd maxillipeds is short and slender, and that of the 

 third (external) maxillipeds is rudimentary or absent. (There are small exo- 

 podites to all the thoracic legs). 



The functional branchiae are 19 on either side arranged as in Solenocera, 

 and there are epipodites on all the thoracic appendages except the last. 



