LEPAS FASCICULARIS. 97 



fucus, which was supposed to have encrusted the scales of 

 the Velellae, to which the Cirripede had originally become 

 attached. Several individuals had their peduncles im- 

 bedded in the same ball, " which floated like a cork on 

 the water." As this species grows into an unusually 

 bulky animal, we here see a beautiful and unique contriv- 

 ance, in the cement forming a vesicular membranous 

 mass, serving as a buoy to float the individuals, which, 

 when young and light, were supported on the small 

 objects to which they originally had been cemented in 

 the usual manner. 



Filamentary Appendages. — Five on each side, of which 

 four lie in pairs at the base of the first cirrus (of these, 

 only three are sometimes developed), and one on the 

 flank of the prosoma. 



Mouth. — Palpi much acuminated. Mandibles with five 

 teeth ; the first not far remote from the second ; inferior 

 point rather broad and finely pectinated. Maxillae with 

 two large, unequal, upper spines, and four regular steps. 



Cirri. — Posterior cirri, with the upper parts of the 

 segments slightly protuberant ; in young specimens, the 

 spines can be seen to consist of five pairs, placed in two 

 converging lines in the upper half of each segment, with 

 numerous minute, latero -marginal, and intermediate little 

 bristles : in large specimens, all these latter have so in- 

 creased in number, that the normal five pair cannot be 

 distinguished, and the front of each segment is covered 

 by a triangular thick brush of bristles, all pointing in the 

 same direction, thus giving a very unusual character to 

 the posterior cirri : the dorsal tuft on each segment con- 

 sists of six or seven large spines, with from one to three 

 dozen fine ones. First cirrus and anterior ramus of second 

 cirrus with broad brushes of bristles. The pedicels of 

 all the cirri are thickly covered with bristles. Caudal 

 appendages smooth, with rounded summits. 



Penis very hairy : vesiculge seminales purple, much 

 convoluted, lying within the prosoma; testes dendritic, 

 scarcely enlarged at their terminal points, purplish ; 



7 



