SCALPELLUM. 85 



Carina moderately bowed inwards, widening gradually downwards from the apex, 

 of which a small portion is filled up solid, and must have projected freely; walls 

 moderately thick ; the two sides of the tectum are rather steeply inclined to each other, 

 and meet in a central line, which is subcarinated with a slightly prominent ridge ; basal 

 margin rectangularly pointed ; parietes nearly flat, about as wide as the tecta, in some 

 specimens perpendicular, so as not to be visible when the valve is viewed from a central 

 dorsal point ; in others, very steeply splayed outwards ; separated from the intra-parietes 

 by a conspicuous rounded ridge, and from the tectum by a nearly equally large ridge, 

 which has generally one, two, or three fine, longitudinal, raised lines on either one or both 

 sides of it : in one specimen the whole surface was thus coarsely and obscurely lined. The 

 intra-parietes are rather wide, extending to the basal margin of the parietes. Depth of 

 valve, measured from the central crest to either inner edge, is about equal to the entire 

 width, as measured from inner edge to edge. The depth compared with the width, 

 though the most conspicuous character, varies a little. Inner edge of valve nearly straight. 

 Length of longest specimen (in Mus. Bowerbank) \Q of an inch. This is the largest carina 

 I have seen in any fossil cirripede. 



5. ScALPELLUM LiNEATUM. Tab. II, figs. 11 and 12. 



S. snperjicie totd carincB lineis tenuibus, rohmdatis, longitudinalibus, proximis, microcos- 

 copicis ohtectd ; crista centralis costd crassiore ; costis duahus vel trihus tectimi et parietes 

 separantibiis ; latitudine valves circa dimidimn altitiidinis aquante ; intra-parietibus latius- 

 culis, nulla costd conspicud a parietibiis separatis ; apice solide repleto, aliquantulum lihere 

 prominente. 



Carina with the whole exterior surface covered with fine, rounded, longitudinal lines, 

 scarcely visible to the naked eye ; with a thicker ridge on the central crest, and Avith two 

 or three similar ones separating the tectum and parietes ; width of valve about half of 

 depth; subcarinated; inter-parietes rather wide, not separated by a conspicuous ridge 

 from the parietes. Apex filled up, solid, and projecting freely a little. 



Lower Chalk of Sussex, Mus. J, Morris ; Mus. J. Sowerby. 



I have seen two carinae in the collections of Mr. Morris and Mr. J. Sowerby so exactly 

 like each other, and having a somewhat different aspect from S. maximum, var. sulcatum, 

 to which they come nearest, that they deserve to be described, whether or not they are 

 really specifically distinct. I long hesitated whether to give them a specific name, and 

 have been, in some degree, influenced in doing so, from the presence of scuta and terga 

 in the Lower Chalk, which indicate a distinct but closely-aUied species. The scutum is in 

 Mr. Morris's collection, and came in the same lot with the carina from Sussex : the tergum 



