POLLICIPES SERTUS. 327 



nence clothed with long spines. Olfactory orifices slightly 

 prominent. 



Cirri. — First cirrus placed near to the second ; poste- 

 rior cirri not much elongated, with their segments slightly 

 protuberant, bearing four pairs of spines, of which the 

 lower pair is small ; spines slightly serrated. In the lower 

 segments, these spines are exceedingly unequal in length, 

 the inner spines on both rami, not being above one fourth 

 of the length of the outer corresponding spine in each 

 pair. The tufts intermediate between these pairs, are not 

 very large : on the lateral upper rims there are some strong, 

 short spines : dorsal tufts with short, thick spines. First 

 cirrus about three fourths as long as the second cirrus, with 

 numerous tapering segments, three or four of the lower 

 ones being thick and protuberant : in the first cirrus there 

 are eleven segments, and in the sixth cirrus, seventeen. 

 Second cirrus, with the anterior ramus slightly thicker 

 than the posterior ramus : a few of the basal segments of 

 both rami are protuberant, and thickly clothed with spines. 

 In the third cirrus, the two rami are nearly equally thick, 

 with some of the basal segments in both clothed, like a 

 brush, with spines. In these brushes on the first, second, 

 and third cirri, most of the spines are doubly toothed, 

 each tooth being simply conical. 



Caudal Appendages, small, much flattened, straight on 

 the exterior side, and curved on the inner side, with a 

 row of short, rather thick spines on the crest, and a few 

 on the exterior margin. 



The Affinities of this species will be given under the 

 head of the following, P. sertus. 



6. POLLICIPES SERTUS. PL VII, fig. 5. 



P. capitido valvarum uno aid pluribus sub-rostro ver- 

 ticillis instructo : laterum pari superiore vix inferioribus 

 longiore: membrand valvas tegente (post desiccationem)fusco 

 rufescente obscuro: rostro dimidiam carince longitudinem 



