FEMALE. 247 



teeth on the crest. Palpi, small, narrow, thinly clothed 

 with bristles. 



Mandibles, with three teeth, of which the first is dis- 

 tant from the second ; inferior angle not much acuminated, 

 pectinated on both edges. 



Maxilla, small, narrow, produced, without any notch, 

 with two large upper spines, of which one is much 

 thicker than the other; on the convex upper margin 

 there are some minute tufts of very small hairs. 



Outer MaxUlce, with few bristles, arranged in a con- 

 tinuous line on the anterior surface ; on the external 

 surface there is a tuft of long bristles. Olfactory orifices 

 situated laterally, forming two flattened, tubular pro- 

 jections. 



Cirri. — First pair placed not far from the second j the 

 three posterior pair not very long, with their segments 

 elongated, not protuberant, bearing four pair of non- 

 serrated spines, with a single short bristle between each 

 pair ; dorsal tufts small, with one spine longer than the 

 others. First cirrus rather short, segments not very 

 broad; second cirrus with the rami nearly equal in length, 

 anterior ramus rather thicker than the posterior ramus, 

 with three longitudinal rows of spines. 



Caudal Appendages. — These are minute, rather broad, 

 not half as long as the lower segments of the pedicels of 

 the sixth cirrus, with four very long spines at the tip. 



Penis. — There is no trace of a probosciformed penis in 

 the four specimens examined j and as this organ is pre- 

 sent in every ordinary cirripede, with the exception of Ibla 

 Cumingii which we know to be exclusively female, so we 

 may infer with some confidence that the form here de- 

 scribed is female, although it is impossible in specimens 

 once dried to demonstrate the absence of the vesiculae 

 seminales and testes. 



Affinities. — This is a very distinct species; it is, how- 

 ever, much more nearly related to S. rutilum, than to any 

 other species ; and next to this, to S. vidgare; from this 

 latter species it chiefly differs in the large scales of the 



