82 BULLETIN OF THE 



like Penceus than like Stenopus hispidus as figured by Boas ; and the species is 

 not so closely allied to PencBus as might be inferred from the description of 

 Benthesicyraus and its place in Bate's arrangement. 



Benthesicymus Bartletti, sp. nor. 



Plate XIV. Figs. 1-7. 



Male. — The carapax is only slightly compressed laterally, and its surface, as 

 well as that of the abdomen, is naked and polished, but is very conspicuously 

 and peculiarly areolated. There is only one spine each side, a prominent and 

 acute branchiostegial, and from this a sharp carina extends back parallel with 

 the inferior margin to near the middle of the carapax, where it is interrupted 

 by a well-marked sulcus which, beginning as the antennal, turns slightly 

 downward, runs back above and contiguous to the carina just described, and 

 then turns down and nearly reaches the inferior margin ; back of this carina a 

 somewhat similar but much less conspicuous cardiaco-branchial carina accom- 

 panied by a slight sulcus extends to near the posterior margin of the carapax ; 

 there is a slight gastro-frontal sulcus at the base of the rostrum ; a very deep 

 and conspicuous transverse gastric sulcus, which slightly notches the dorsum at 

 about the middle of the carapax, extends in an even curve downward and for- 

 ward, as the gastro-hepatic, and joins the hepatic sulcus a little way back of the 

 branchiostegial spine ; and back of this sulcus there is a distinct but much less 

 conspicuous cervical, extending from very near the middle line, at about a third 

 of the way from the transverse gastric sulcus to the posterior margin, down- 

 ward to the cardiaco-branchial suture. In front of the transverse gastric sulcus 

 there is a sharp dorsal carina which rises into a lamellar crest and terminates 

 in a short and laterally compressed rostrum armed above with two sharp teeth 

 of which the posterior is slightly back of the orbit and the anterior apparently 

 about half-way between it and the tip, which is slightly broken but appears to 

 have terminated in an acute point about two thirds of the way from the base 

 to the tip of the eyestalk. Both edges of the rostrum are ciliated. Back of 

 the gastric sulcus the dorsum is broad and evenly rounded transversely. 



The eyestalks (PI. XIV. figs. 1, 1') are less than half as long as the antennal 

 scales, slender, strongly compressed vertically, with a small obtuse dentiform 

 prominence at the middle of the inner side, and just in front of and outside of 

 this a small spot of black pigment showing faintly on the upper but conspicu- 

 ously on the lower side. The eyes themselves are scarcely wider than the stalks, 

 but are less compressed vertically, though still much broader than high, dis- 

 tinctly faceted, and dark brown in the alcoholic specimen. 



The peduncles of the antennulse (Figs. 1, 1') are more than half as long as 

 the antennal scales, and essentially as in the species of Pencnus. The first seg- 

 ment is considerably longer than the two others taken together, is expanded 

 laterally and deeply excavated above to fit the eye, and the outer margin is 

 armed with an acute tooth opposite the extremity of the eye and another at the 



