GASTROCH.ENA. 129 



breviusculo ; umbonibus decurvis terraiiialibus. — Very thick 

 and ventricose, rather oval, obtusely pointed at the back and 

 truncated in front by the depression of the umboes, which 

 are terminal. 



13. DENTicuLATA, f. 7, Deshciyes. — Breviter cuneiformis, 

 veatricosa, antice striis elevatis minute denticulatis sculpta. — 

 Remarkable for the denticulated ridges with which the 

 anterior area is sculptured. 



14. LAEVIGATA, f. 26, Deshayes. — Brevis, subcompressa, 

 Isevis oblique cuneiformis. — Resembling sp. 1 in form, but 

 small and quite smooth. 



15. HDMiLis, f. 27, Deshayes. — G. Icevigatce similis, sed 

 tenuiter concentrice striata. — Similar to G. Icevigata in 

 shape, but differing in being concentrically striated. 



16. MACROCHISMA, f. 29, Deshciyes. — Brevis, ventricosa, con- 

 centrice striata, antice producta, acuminata ; hiatu brevi, 

 lato. — Short, ventricose, concentrically striated, anteriorly 

 produced, acuminated ; hiatus broad and rather short. 



17. HYALINA, f. 24, Deshayes. — Tenuis, semipellucida, 

 angusta,elongata; margine dorsali parum elevato. — Elongated 

 and very narrow, particularly in front, acuminated at the 

 back, small and very transparent. 



18. SPATHULATA, f. 6, Deshayss. — Tenuissima, compressa, 

 cuneiformis, angusta, postice rugata, subtruncata, antice 

 acuminata. — Very thin, flat, wrinkled and truncated poste- 

 riorly ; rather pointed in front. 



19. INTERRUPTA, f. 22, Deshayes. — Grracilis, tenuis, com- 

 pressa, postice sulcis concentricis divisa, ad terminum sub- 

 truncata. — The figure is unfortunately a little more trun- 

 cated than it should be. The posterior part of the shell is 

 rather distantly and flatly grooved. 



20. TENERA, f. 28, Deshayes. — Gracilis, tenuis, modiolifor- 

 mis, tenuiter striata ; margine dorsali elevato ; area dorsali ad 

 terminum subtruncato. — Very thin and narrow, with a rather 

 roundly truncated end. 



21. RuPELLii, f. 15, Deshayes. — Solida, oblonga, postice 

 obtuse acuminata, antice late truncato ; hiatu maximo ; um- 

 bonibus terminalibus tumidis. — In form this species has 



