268 SUTURE. 



agrees with the family Nayades of Lamarck, and contains the 

 genera Anodon, Unio, and Cardita. 



SUB-OSTRACEA. Bl. The second family of Lamellibranchiata, 

 Bl. the shells of which are described as of a compact texture, 

 sub-symmetrical; with the hinge rather complex; one single, 

 sub-central, muscular impression, without any traces of pal- 

 leal impression. This family corresponds with the Pectenides 

 of Lamarck, and part of the genus Ostrea in the system of Lin- 

 nseus. It contains the genera Spondylus, Plicatula, Hinnites, 

 Pecten, Pedum, Lima. 



SUB-SPIRAL. Not sufficiently spiral to form a complete volution. 



SUBULA. Bl. {An awl.) A generic name under which M. De 

 Blainville includes Terebra maculata, Auct. f. 428, together 

 with nearly all the species of Terebra, enumerated by Lamarck 

 and other authors ; only leaving in the latter genus those species, 

 which being more bulbous, or ventricose, nearly resemble Bucci- 

 num in general form. These last mentioned species, such as 

 Terebra buccinoidea, (fig. 247) have been formed into a new 

 genus by Mr. Gray, under the name Bullia. If both these genera 

 were adopted, the genus Terebra would be extinct. 



SUBULATE. (Subula, an awl.) A term applied to shells which 

 are long and pointed as in Terebra. Fig. 427, 428. 



SUCCINEA. Drap. (Succinum, amber.) Fam. Colimacea, Lam. 

 Limacinea, Bl. Sub-genus, Cochlohydra, Fer. — Bescr. Ovate, 

 rather elongated ; apertui'e large, entire, longitudinal ; spire 

 short ; outer lip thin, continuous with the thin, sharp-edged co- 

 lumella ; inner lip spread over a part of the body-whorl. — Obs. 

 The shells belonging to this genus of partly amphibious mollusca, 

 are distinguished from Limnaea by not having a fold on the 

 columella The S. amphibia is of a bright amber colour. Fig, 

 265, 266. Temperate and tropical climates. 



SULCATED. (Sulcatus, lat.) Having grooves or furrows. 



SULCI. Grooves or furrows. 



SUTURE. {Sutura, lat.) A seam, stitch, joining together. Ap- 

 plied particularly to the line which marks the joining of the 

 whorls of the spire. The suture is distinguished as simple, as in 



