DONAX. 300 



angles are radiating grooves, behind them both is a narrow area 

 with undulating concentric ridges. 



25. striatus (f. 52), Linn. — Testa oblongfi, carina, purpura- 

 scente dense striata, antice acuminata, postice acute biangulata, 

 declivi, area postangulari complanata, minutissime striata, margine 

 ventrali denticulato, medio convexo, antice et postice subincurvo. 

 — Sharply angular, the angle being duplicate towards the ventral 

 edge of the dorsal slope, the postangular area very flat. There 

 is no reason to doubt the identity of Deshayes' Lamarclcii with 

 this. 



26. saxuh'm (f. 110), Reeve. — Testa B. contiim simili, sed 

 striis elevatis radiantibus sculpta, postice valde declivi, angulata. 

 — Differing from I), striata in the ridge-like strife with which it 

 is rayed. It is also more angular and truncated posteriorly. 



27. variabilis (f. 37, 38, 39), Say. — Testa parva, tumida, 

 tenuistriata, varie picta, antice oblonga, prope marginem attenua- 

 tim acuminata, postice leviter angulata, area postangulari convexa, 

 margine ventrali medio convexo. — A little, tumid, finely striated 

 shell, variously coloured, distinguished by a pccnliar pinched aud 

 pointed appearance towards the anterior extremity. 



2S. bellvs (f. 40, 41), BesJi. — Testa oblonga, tenuiter striata, 

 alba fulva seu purpureo radiata, postice brevi, declivi, obtuse 

 angulata, margine ventrali rectiusculo. — Kesembling I), variabilis, 

 but gradually sloping in front, with the ventral margin rather 

 straight. 



29. angustatus (f. 44), Sowb. — Testa albido-purpurascente, B. 

 variabili simili sed magis compressa et elongata. — Resembling 

 D. variabilis, but much more elongated. 



30. LjEvigatus (f. 30, 31, 32), Besli.— Testa solida, polita, 

 fulva, partim purpureo fasciata, tumida, leviter striata, antice 

 acuminatim rotundata, postice brevi, obtusa, medio intlata, um- 

 bonibus obtusis, margine ventrali convexo. — A smooth, polished, 

 obese, obtuse shell, of a fawn-colour, banded and tipped with 

 purple. 



31. Saigonensis (f. 45), Crosse et Fisck. — Testa brevi, com- 

 pressa, obtusa, antice rotundata, postice obtuse angulata, posf 

 angalum minute cancellata, intus purpureo et aurantio variegata ; 

 dentibus lateralibus magnis; latere postico rectiusculo, convexo. 

 Resembling D. laevigata in form, but finely cancellated on tin 

 area behind the angle. 



vol.. in. I i: 



