32 Dr. T. Scott on neiv and rare 



Eusirogenes is distinguished, and I think undoubtedly belongs 

 to that genus ; but, as indicated below, it differs in some 

 respects from the species described by Mr. Stebbing. Un- 

 fortunately Eusirogenes dolicliocarpus, Stebbing, like the 

 form mentioned here, was described from a single damaged 

 specimen, and the author was unable to give so full a descrip- 

 tion of it as would have been desirable. Had the specimens 

 in both cases been perfect, other differences besides those 

 referred to might have been noticed. 



In the specimen now recorded the cephalon was very 

 imperfect and both pairs of antennae were gone. 



The mandibles, maxillae, and maxillipeds, as shown by the 

 drawings, are somewhat similar in structure to the same 

 appendages in E. dolicliocarpus. 



The gnathopods are unequal in size, the first pair being 

 somewhat larger than the -second. In the first pair the basal 

 joint is elongated and tapers towards the distal end, where 

 it is only half as wide as at the proximal end ; this joint is 

 furnished with a few moderately long and slender bristles. 

 The third and fourth joints are short. The carpus or fifth 

 joint is elongated and slender, its length is equal to about 

 four-fifths of that of the second joint ; the superior margin of 

 the joint is nearly straight, while the lower curves downward 

 from both ends to form a small triangular process, the apex 

 of which is rather nearer the proximal than the distal extre- 

 mity and bears one or two moderately long and slender 

 bristles. The distal half of the lower margin forms a shallow 

 concavity to receive the large propodos when folded back 

 upon the carpal joint. The propodos is about twice as long 

 as broad, and with the outer and inner edges nearly parallel; 

 the outer edge or palm terminates below in a distinct though 

 small angular projection, from which springs a moderately 

 long and stout spine; the dactylus is long and slender, 

 slightly curved and finely serrated on the inner edge (fig. 4). 

 The second pair of gnathopods, though smaller than the first, 

 are somewhat similar to them in structure; in this pair, 

 however, the second joint is narrow, with the margins nearly 

 parallel, and provided with a number of marginal bristles; 

 the carpal joint is rather longer than the second, and the 

 bristles at the apex of the triangular process of the lower 

 margin are more numerous ; the propodos also differs from 

 that of the first pair in that it expands and becomes rather 

 wider posteriorly (fig. 5). 



The remaining pereiopods were imperfect, but appeared to 

 be all elongated and slender as in E. dolicliocarpus. The 

 coxal plates of the gnathopods and of the first and second 



