THE SESSILE BAENACLES. 



265 



tudinally, and there are no incisions or lobes in the periphery, un- 

 less the two varieties placed under C. mftnati belong to this species. 



There seems to be but little racial differentiation in C'. testudinaria, 

 though very large series might show more than I can see at present. 

 The Atlantic specimens, as a general rule, have fewer and coarser 

 transverse sutural ridges than those of the Pacific. Rarely they are 

 almost obsolete. When old the wall is usually higher, especially the 

 rostrum, which has a more arched profile; but this is not obvious in 

 smaller examples. The basal septa are often, but not always, thicker. 

 The orifice is sometimes longer, but varies from about one-third to 

 nearly one-half the total length. A specimen of about the maximum 

 size reached on our coast measures 48 mm. in carinorostral diameter, 

 height 18 mm. (pi. C2, fig. 2). 



The only one I have seen from the Galapagos is veiy large and 

 low, 78 mm. long, 19 mm. high. The body-chamber is less than half 

 of the basal diameter (pi. 62, fig. 1). A similar specimen 60 mm. 

 long was taken in San Bartholome Bay, Lower California. 



In the Gulf of California and at Cape St. Lucas there may be a 

 small race. At all events, in three lots, about 25 specimens, the maxi- 

 mum length is about 28 mm. (pi. 62, fig. 3). In these, and all west 

 American specimens seen, the transverse ridges in the radii are 

 narrower and slightly more numerous than in Atlantic examples. 



i Specimens in the collection of the Academy of Natural Sciences of Philadelphia, the records inserted 

 hero to show its occurrence in the Middle States, etc. 



CHELONIBIA MANATI Gruvel. 



1903. ritrlonnltia nninati GRUVEL, Nouvelle Archives elu Museum d'Histoire 



Naturelle, ser. 4, vol. 5, p. 11G, pi. 2, figs. 14, 17, IS ; pi. 4, figs. 15, 1G. 



1905. Clictonobid itxmaU GRUVKL, Monographie ties Cirrhipedes, p. 207, fig. 



2976. 



Tape. Museum d'Histoire Naturelle de Paris, from the Congo 

 coast, abundant on skin of Manatus senegalensis. 



