24 CIRRIPLDIA. 



In Scalpellum Per onii, and villosum, the males are but little 

 abnormal, for if classified independently of their sexual 

 relations, they would be considered as immature speci- 

 mens of a new genus, standing next to Scalpellum; in 

 Scalpellum rostratum, the male would form another and 

 rather more distinct genus. The males, in the latter, 

 are attached to the other sex, between the basal edge 

 of the labrum and the adductor scutorum muscle ; but in 

 S. Peronii and villosum they are attached lower down, in 

 the furrow between the two scuta, and are thus protected: 

 in these three species, the internal parts of the male present 

 nothing particular. In Ibla, the males are attached low 

 down within the sack of the female ; they may be said to 

 consist of a mouth surmounted on a long peduncle, for 

 there is no capitulum or general covering, and the whole 

 thorax is in a rudimentary condition, the cirri being reduced 

 to two distorted pairs. As these males certainly moult 

 several times and grow a little, they must feed; and as they 

 have no cirri fit for action, they must seize their food by 

 the contortions of their peduncle, which we know homolo- 

 gically consists of the three first segments of the head. 

 The movements of the peduncle must, also, supply those of 

 the probosciformed penis, almost invariably present with 

 other Cirripedes, but here absent. If compelled to class 

 these males without regard to the female, great difficulty 

 would be experienced ; we could hardly place in the family 

 of the Lepadidse, a Cirripede without a capitulum, and 

 without cirri, those very organs which give their name to the 

 class, and with a thorax reduced to the dimensions of a lower 

 lip ; yet, if the presence of a peduncle did determine the 

 classifier to place these males amongst the Lepadidae, then 

 undoubtedly the character of the mouth, &c. would fix their 

 position next to Ibla. 



The males of Scalpellum vulgar e, ornatum, and rutilum, 

 resemble each other in all essential points, and differ won- 

 derfully in appearance and structure from all ordinary Cir- 

 ripedes. They consist of a minute flattened bag with a 

 small orifice at the summit, and at the lower end attached 

 by the cemented pupal antennae. On each side of the orifice, 

 there is a pair of calcareous beads, representing the two 



