180 SCINTILLA. 



39. Sc. hydatina, (f. 56, 57), Desk. — Testa hyalina, tenuissi- 

 ma, pallide fulva, compressa, subovali ; tertninis rotundis ; mar- 

 gine dorsali utrinque aperto. Obs. Very transparent and flat, 

 oval, and open at the dorsal edge. 



40. Sc. hydrophana (f. 62), Desh. — Testa, semipellucida, pal- 

 lide fulva, subovali, compressa, quam Sc. hgtlatina magis oblonga ; 

 termiuis declivis, paulo apertis. Obs. Eather less pellucid and 

 more oblong than Sc. hydatina. 



41. Sc. crocea (f. 63), Desh. — Testa aurantia, compressa, pellu- 

 cida, subquadrata; termiuis oblique truncatis; apiceacuto; margi- 

 nibus dorsalibus paulo apertis. Obs. Platter, more transparent, and 

 longer in proportion to its height than Sc. succinea, and with the 

 dorsal margins a little open. 



42. Sc. Cuvieri (f. 59, 60), Desh.— Test& tenui, subrotunda, 

 subinflata, concentrice leviter striata, pallide fulva, leviter radiata; 

 margine dorsali ad latera paululum aperto ; latere antico brevius- 

 culo, paululum angustato. Obs. This shell is nearly circular, with 

 the anterior side slightly contracted. 



43. Sc. Timorensis (f. 61), Desh. — Testa subquadrata, flavida, 

 compressa; margine dorsali ad latera paululum aperto, termiuis 

 subtruncatis, margine ventrali rectiusculo. Obs. Much more square 

 than the preceding. 



44. Sc. flavida (f. 64), Desh. — Testa pallida, quam Sc. 

 Timorensis paululum magis rotunda, antice haud tantum truncata. 

 Obs. More pale, thin and rounded than Sc. Timorensis. 



45. Sc. vitrea (f. 68), Desh. — Testa tenuissima, pallida, faseiis 

 opacis cincta, pellucida, compressa, subquadrata ; terminis obli- 

 que truncatis. Obs. A very flat, scale-like transparent shell. 



46. Sc. squama (f. 65), Desh. — Testa alba, pellucida, com- 

 pressa, concent-rice undulata, ovali, margine dorsali ad latera aperto ; 

 latere antico breviusculo, subtruncato. Obs. This delicate, trans- 

 parent, scale-like shell is concentrically undulated. 



47. Sc. pellicula (f. 66, 67), Desh. — Testa oblique ovali, 

 alba, pellucida; undis concentricis magnis, lateribus subtruncatis. 

 Obs. A more oblique shell than Sc. squama, with the centric ridges 

 larger. 



