MARINE MOLLUSCA OF THE UNITED STATES. 199 



Genus TEREBRATULINA, Orb. 

 Comp. Rend., xxv. 308. 18-47. 



1. T. SEPTENTRiGNALis, Coutliouy. Figs. 548, 549. 



(Terebratula.) Bost. Jouru. Xat. Hist., ii. 65, t. 3, f. 18. 



Terebratula cajmt-serpentis, Gould (non Auct.), Invert. Mass., edit. 1. 141. 

 1841. 



Shell obovate, whitish oryellowish-white, thin, translucent; upper 

 valve truncated horizontall)' at the apex ; foramen large, one side 

 completed by the apex of the lower valve ; surface covered by 

 minute radiating strire. 



Length 15, Avidth 12 mill. 



Maine, nortlnoards. 



Family RHYNCHONELLID^. 



Shell with radiating ribs, the arm supports long, slender, simple, 

 and gently curving towards each other; no area; the opening for 

 the pedicle usually' completed by two small pieces ; animal with 

 elongated spiral arms. 



Genus KHYNCHONELLA, Fischer. 

 Mem. Soc. Imp., Moscow, 11. 1809. 



1. R. PSITTACEA, Gmelin. Fig. 550. 



{Ajiomia.) Syst. Nat., 3348. 1790.* 

 Shell subtriangular, thin, inflated, brownish or greenish ; beak 

 produced and curved ; surfiice radiately finely striated. The 

 internal processes consist of two slender curved parallel prongs 

 proceeding from the base. of the teeth of the upper valves. 

 Length 12, width 8 mill. 



Neiofoundland, northwards. 



Family LINGULID^. 



Shell pedunculate, peduncle passing between the valves ; mar- 

 ticulate, subequivalve ; brachia unsujiported by calcified jirocesses. 



Genus GLOTTIDIA, Dall. 

 Am. Journ. Couch., vi. 157. 1871. 



Shell linguiform, smooth, elongated ; neural valve furnished 

 internally with two sharp narrow incurved lamina?, diverging from 



