SOLENOOURTUS. 279 



4. SoLENiMTA. No teeth, epidermis over-reaching the shell. 



Pig. 68. 



5. GrLYCiMEEis. Thick, fulcrum of the ligament prominent. 



Fig. 67. 



6. Lepton. Elat, scale-shaped. Fig. 62. 



7. NoTACULijfTA.. Umbones nearly central ; covered by a 



thin epidermis. Fig. 63. 



8. Gi/AUCOKOME. Oval, margins close. Fig. 64. 

 SOLENl^LLA. Sowerby, 1832. (Solen.) Fam. Arcacea, Lam. — 



Descr. Oval, equivalve, subequUateral, compressed, covered with 

 a thin, shining, olive-green epidermis ; hinge with three or four 

 anterior, and numerous sharp posterior lateral teeth, arranged 

 in a straight line ; muscular impressions two, lateral ; paUeal 

 impression with a large sinus ; ligament external, prominent, 

 elongated. — Obs, This genus partakes of the characters of the 

 genus Nucula, and of the family Solenacea, A few specimens 

 of the only species known (S. Norrisii) were dredged by Mr. 

 Cuming at Valparaiso. PL vii. fig. 138. 



SOLENIMTA. Lam. (Solen and Mya.) Fam. Mactracea, Lau. 

 Pyloridea, Bl. — Descr. Equivalve, inequilateral, transversely 

 oblong, rounded at the extremities with the umbones near the 

 posterior side, covered with a shining brown epidermis ex- 

 tending beyond the edges of the shell ; hinge without teeth ; 

 ligament partly internal, placed in the margin of an oblique, 

 flattish, posterior rib ; muscular impressions two, distant, lateral. 

 From the Mediterranean, Australian, and Atlantic Oceans. — 

 Obs. Solenimya differs from Solenocurtus and the true Solens 

 in having the posterior side of the shell the shortest ; in the 

 internal ligament ; and in being destitute of teeth. It resembles 

 Grlycimeris, but is not thickened. Solenimya radiata. PL iii. 

 fig. 68. 



SOLENOCTJETUS, Bl. (Solen and curtus, short.) Fam. Pylo- 

 ridea, Bl. Solenacea, Lam. Descr. Oval, elongated, equivalve, 

 sub-equilateral, with the edges nearly straight and parallel, and 

 the extremities rather truncated ; umbones not very prominent, 

 sub-central ; hinge with or without two or three rudimentary 



