176 Rev. A. M. Norman on Recent Eryontidse. 



Male. Anterior margin of carapace with a strong central 

 spine, flanked on each side with another spine 5 lateral margin 

 bearing seven spines on anterior (hepatic) portion, five spines 

 on the middle division, and about twenty on the branchial 

 portion ; central dorsal line spined, spines arranged in single 

 or double files, thus — 1 (the rostral), 1, 1, 2,2, 2,2*; hinder 

 margin bearing six spines — the median pair, and on each side 

 of these two spines ; a curved row of five spines passes back- 

 ward from the ocular notch ; and a ridge crowned with about 

 fourteen minute spines runs along the branchial region parallel 

 with the lateral margin ; still more minute spines are also 

 present on the ridges which divide the gastric from the 

 cardiac and branchial regions and other parts of the carapace. 

 The pleon has the first five segments centrally carinated, 

 with a large forwardly curving spine at the anterior end of the 

 carina of each segment ; this spine attains its greatest de- 

 velopment on the fourth and fifth segments ; sixth segment 

 bicarinated, the carinas nodulous; the sides of all the segments 

 ornamented with small rounded tubercles. Telson gradually 

 tapering to an acute termination, its anterior portion with a 

 central carina, while the hinder portion is bicarinate, the 

 carinas slightly serrulate. Gnathopods imperfect ; the base of 

 one remains as far as the middle of the meros, the outer 

 margin of portion of the meros which remains bears several 

 small spines. Last pereiopods with the extremity simple, 

 styliform, much shorter and more slender than the preceding 

 pair. First pleopods one-branched, simple, spoon-shaped, the 

 expanded portion thin and transparent, with a central rib. 

 Length 60 millims. 



Female in all its general characters and the structure of its 

 limbs closely resembling the male just described, but differs 

 as follows: — Cephalothorax bearing on front margin a pair of 

 central spines (instead of a single spine) ; lateral margin with 

 the spines 6, 3, 8 ; central dorsal row 2 (rostral), 1, 2, 1, 2, 

 2, 2 ; no spines on hinder margin, except the central pair ; 

 five spines on hepatic and gastric regions as in male ; ridge 

 on branchial region with only five spines ; the smaller spines 

 present on the carapace of the male are absent or evanescent. 

 The pleon is carinated and armed exactly as in male, and only 

 differs in the minute tubercles on the sides not being deve- 

 loped. Ocular notch deeper than in male. First pereiopods 

 with two spines on the outer margin of the meros, and a 



* These are only the more prominent spines ; the intermediate spaces 

 between them are furnished, as are all other parts of the carapace, with 

 minute spines, any one of which, a little more developed, would make 

 such a spine as would be counted in the row. 



