CIRRI AND CAUDAL APPENDAGES. 43 



long spines on the anterior face, with generally some 

 minute spines (occasionally forming a tuft) intermediate 

 between them : on the dorsal surface, in the upper- 

 most part of each segment, there is a tuft of short spines 

 generally mingled with some longer, finer ones : on the 

 inner side of each segment, on the upper rim, there are 

 generally a few extremely minute and short spines. From 

 the increase of these latter and of the intermediate spines, 

 the antero-lateral faces of the segments of the first cirrus, 

 and of the lower segments of the anterior ramus of the 

 second cirrus (PI. X, fig. 25), are almost always thickly 

 paved with brush-like masses of spines. The lower seg- 

 ments of the anterior ramus of the third cirrus is generally, 

 though not always, thus paved : these paved segments 

 are much broader than the others. The posterior rami 

 of the second and third cirri are often in some slight 

 degree paved, though in other cases they resemble the 

 three posterior pair of cirri. The two segments of the 

 pedicels have bristles on their anterior faces, essentially 

 arranged on the same plan as on the segments of the 

 rami : the bristles are generally not so symmetrically 

 arranged on the pedicels of the second and third cirri, as 

 on the three posterior pair. There are some exceptions 

 to the foregoing general rules : in the posterior cirri of 

 Alepas cor nut a, there is only one pair of long spines to 

 each segment (fig. 28) ; in Bichelaspis Zotvei, there are 

 eight pair; in Zep as fascicular is, in old specimens, the 

 segments are paved with a triangular brush of spines ; 

 the upper segments in Pcecilasma eburnea support small 

 oblong brushes; and, lastly, in Pcecilasma jissa (fig. 29), 

 and crassa, the spines form a single circle round each 

 segment, interrupted on the two sides. These spines are 

 often doubly serrated or plumose : many of them on the 

 protuberant segments of the first three pair of cirri, are 

 sometimes coarsely and doubly pectinated. 



Caudal Jpp enclaves. — These are present (PL X, 

 figs. IS to 24) seated on each side of the anus, in all the 

 genera, except in Conchoderma, Anelasma, and Scalpellum 



