28 FOSSIL CIRRIPEDIA. 



different aspect from the ordinary varieties, and do really differ in the sutural edges of the 

 alee being crenated, and in the greater narrowness and obliquity of the radii ; but these 

 points are all commonly variable. I have not seen any large specimens of the variety 

 (fig. 2c), plicatus, so as to compare them with the large specimens of the normal form, yet 

 I can hardly entertain any doubt, considering their agreement in so many important 

 points, that I have rightly treated these forms as mere varieties ; it is unfortunate that 

 none of the specimens of the var. plicatus seen by me have had opercular valves, as their 

 presence would have removed all shadow of doubt. I have given a drawing, enlarged seven 

 times, of some very young shells (fig. 2d), adhering in numbers on Pecten Gerardii, which I 

 believe belong to the plicated variety of our present species, but which are much too young 

 to be identified with certainty. 



Affinities: this is a strongly characterised species, and nearly allied only to the 

 following species, B. dolosus. The furrows on the scuta in some degree resemble those on 

 the recent B. lavis, but there is no alliance with that species. It is certain that amongst 

 recent species, the chief affinity is with B. Hameri and amaryllis. 



9. Balanus dolosus. Tab. II, fig. 3a — 3d. 



B. nee parietibus, nee radiis poris perforatis ; basi poris magnis perforata, radiorum 

 marginibus superioribus obliquis, lavibus ; aciebus suturalibus item lavibus ; tergi calcare 

 non admodum brevi, l valvce latitudine. 



Neither walls nor radii permeated by pores ; basis permeated by large pores ; radii with 

 their upper margins oblique and smooth ; sutural edges smooth ; tergum with the spur not 

 very short, broad as one third of valve. 



Fossil in Red (Sutton) and Mammaliferous Crag ; Mus. S. Wood, Bowerbank, Lyell, J. de C. Sowerby, 

 Henslow, &c. Mammaliferous Crag, Postwick, near Norwich, Mus. Lyell. 



This species so closely resembles B. bisulcatus, both externally and in all the essential 

 characters of the parietes, radii, and basis, that it is quite superfluous to describe 

 again these parts. The spcwle characters are derived from the opercular valves, which 

 present well defined distinctions, found by me constant in several specimens of both 

 species. B. dolosus, like B. bisulcatus, has quite smooth and deeply plicated varieties, 

 often adhering to the same univalve. The ribs on the inner surfaces of the parietes are 

 remarkably prominent, as shown in the drawing (fig. 3d) of the inside of the rostrum. I 

 think the upper margins of the radii are in this species rather more oblique than in 

 7?. bisulcatus. The sutural edges of the radii are marked by the finest striae, representing 

 septa. The sutural edges of the alas are generally distinctly crenated. The basis is often 

 slightly cup-formed, and very plainly porose (fig. 3b) : its upper surface is marked by 



