50 STALK-EYED CRUSTACEA. 



branaceous, as in the genus Derniahims Brandt.* In all essential structural 

 features, however, it agrees with the preceding species {Lcpiolithodcs aspcr) 

 and conforms to the genus LeptoUtliodes. 



A LeptoUtliodes, in some respects interinediate between L. louijipcs and 

 L. asper, inhabits both the east and west coasts of the North Pacific (British 

 Columbia and Japan). From this species (which is apparently undescribed) 

 both L. longipes and L. asper of the tropical Pacific coast of America are 

 probably derived. 



LITHODES Latr. 



Gen. Crust., 1. 39, 1806. 



Lithodes panamensis Fax. 

 Plate X., Fig. 1, T T' 1". 



Bull. Mus. Comp. Zool., XXIV. 166, 1S93. 



Carapace subpiriform, of about equal length and breadth ; gastric and 

 branchial regions very convex ; a deep depression on each side at the an- 

 terior limit of the branchial areas, and another between the gastric and 

 cardiac areas. Rostrum cylindrical, terminating in three spines or teeth, 

 one of which is median, the other two lateral ; a long horn, slightly up- 

 curved, is given off from the lower side of the proximal end of the rostrum. 

 The whole surface of the carapace is rough with low warty jjrotuberances ; 

 the gastric region bears two pairs of spines, the anterior pair separated by a 

 greater interval than the posterior pair. Two small spines on each branchial 

 area and two on the intestinal region. The orbit is bounded externally by 

 a prominent spine, and there are five more spines on the lateral border of 

 the carapace ; viz., one at the antero-lateral angle, one on the hepatic region, 

 and three on the branchial. Besides these, there is a rudimentary lateral 

 spine near the anterior limit of the branchial region. The posterior margin 

 of the carapace is tuberculated, not spinose. The third segment of the anten- 

 nular peduncle is equal to the first segment in length and considerably 

 longer than the second segment. The antennas are about ef|ual in length to 

 the carapace without the rostrum ; the second segment is armed with a long 

 and sharp external spine ; there is, moreover, on the antenna of the right 

 aide a movable thorn-like acicle equal in length to the last two segments of 

 • Bull. Phys.-Math. Acad. Iinpir. Sci. St, Petersbourg, VIII. 208, 1850. 



