6 TEREBRIDAE. 



spirally twisted, forming a false umbilicus, pervious to the apex 

 of the spire, much produced anteriorly ; aperture somewhat 

 effuse. A. aciculata, Lam. 



Under Terebra, they admit the subgenus : 



MYURELLA, Hinds. Whorls furnished posteriorly with a tuber- 

 culated zone, anteriorly transversely sculptured, or, very rarely, 

 smooth ; columella tortuous and produced anteriorly. 



T. affinis, Gray. 



To complete the group of subgenera proposed in Terebridae, I 

 here add : 



IMPAGES, Smith. Shell subulate, whorls entire, more or less 

 longitudinally striate or punctate, suture indistinctly separated, 

 with a narrow callous band above it. This name is substituted 

 for Leiodomus, Gray, not Swainson ; Swainson's group belonging 

 to Bullia. The character usually (but not always) obtains in 

 the typical T. caerulescens, but in the other species quoted by 

 Mr. Smith as members of this group it is mostly absent. 



M. Deshayes, in 1857, described a number of new species in 

 the "Journal de Conchyliologie," and in J859 he published, in 

 Zool. Proc. London, "A General Review of the Genus Terebra, 

 and a Description of New Species." Excluding doubtful and 

 unidentified forms, 221 species are enumerated, of which 90 are 

 described by this author. 



In the systematic arrangement of the species Deshayes mainly 

 follows H. and A. Adams, thus (I add characteristic examples) : 



First Division. (Acus, Humphrey.) 



A. Shell buccinoid. (S. Gr. EURYTA, Ad.). T. aciculata, Lam. 



B. Shell elongated, subulate. T. Senegalensis, Lam. 



C. Shell subulate, whorls flattened, usually striate at the suture. 



a. Aperture narrow. 



1. Finely striute at the suture. T. cuspidata, Hinds. 



2. Plications continuous from whorl to whorl. 



T. concinna, Desh. 



b. Aperture dilated at the base. 



1. Whorls smooth or finely striate. T. cxrulescens, Lam. 



2. Plications continuous from whorl to whorl. 



T. tfrigilata, Linn. 



