496 VERRUCJD^E. 



found only in the valves of the Lepadiclae. Verruca differs 

 both from the Lepadidae and Balanidae in the whole shell 

 or external covering, having no other muscle besides the 

 adductor scutorum. In the characters derived from the 

 animal's body, Verruca approaches both families ; but in 

 the absence of branchiae, and in the great development of 

 the caudal appendages, perhaps it comes rather the nearest 

 to the Lepadidae. Whatever affinity there is to the Balanidae, 

 it is much stronger to the sub-family Chthamalinae than to 

 the Balaninae ; though the non-bullate labrum, in three of 

 the species, and the great dissimilarity of the third cirrus 

 from the three posterior pairs, at first seems to indicate a 

 closer relationship to the Balaninae ; but the labrum is never 

 notched, as in the latter sub-family, and in V. nexa it is 

 bullate, and supports palpi of only small size. The dis- 

 similarity, also, of the third pair of cirri, compared with the 

 posterior pairs, is hardly greater than in Oldham aim inter- 

 textus and ChamcBsipho columna, members of the Chtliama- 

 lince, though abnormal in this one respect. Perhaps even 

 a special affinity is evinced between certain species of 

 Chthamalus, as C. intertextus, and certain species of Verruca, 

 as V. nexa, namely, in the interfolding sutures and in the 

 very peculiar, inflected basal margin of the walls. Upon 

 the whole, the affinities of the Verrucidae are complex, and 

 nearly equally divided between the two great families of 

 Balanidae and Lepadidae, or sessile and pedunculated 

 cirripedes. 



Genus — Verruca. PL 21. 



Verkuca.* Schumacher. Essai d'un Nouveau Syst. Class., 1817. 



Clysia. Leach. Journal de Physique, torn. 85, July, 1817; Clisia, 

 Leach, Eucyclop. Brit. SuppL, vol. 3, 1824; Clitia, 

 G. B. Sowerby, Genera of Recent and Fossil Shells. 



* According to Bock, in the c Katurforscher' of 1778, this term was used by 

 Rumph for a Chelonobia, but as it was before the adoption of the binomial 

 nomenclature, according to the Rules, it may be passed over, and does not 

 interfere with the priority of Schumacher. 



