var. atrata Chemnitz. 



Chemnitz. Conch. Cab. Vol. V, p. 158, PI. 175, fig. 1729, 1730, 173 1. 



Reeve. Conch. Ic. Vol. I, Delphinula, fig. 4. 



PiLSBRY. Man. of Conch. Vol. X, p. 267, PI. 66, fig. 15. . 



Stat. 86. Dongala, Palos-bay, Celebes. Reef, i Spec. 

 Stat. 225. South Lucipara-island. Reef, i Spec. 

 Stat. 250. Kur. Reef, i Spec. 



The last-mentioned specimen is very typical, that from Stat. 86, approaches the type by 

 its aperture. It is indeed no easy task, to separate a large number of specimens. Troschel who 

 has described the radula of both forms, found no important differences between them, and 

 suggests, also on this ground, that they may be merely varieties of one species. 



2. Delphinula sphaerula Kiener. PL IX, 'ag. 3. 



KlENER. Coq. Viv. Vol. IX, Delphinula, p. 5, PL 3, fig. 3. 



Reeve. Conch. Ic. Vol. I, Delphinula, fig. 13. 



PiLSBRY. Man. of Conch. Vol. X, p. 268, PL 67, fig. S; PL 68, fig. 20. 



Stat. 99. North-Ubian. 16 — 23 M. Lithothamnion-bottom. 2 Spec. 

 Stat. 133. Lirung, Salibabu-island. Up to 36 M. Hard sand, i Spec. 

 Stat. 240. Banda. 9 — 45 M. Lithothamnion-bottom. 2 Spec. 



The specimens collected by the "Siboga" are young, those from Stat. 99 even very 

 young; in consequence the characteristic appendages are not very conspicuous. The operculum 

 does not differ materially from that of D. laciniata Lam. In the largest specimen, with a diameter 

 of 2 2 Mill, (without the appendages) it is more delicate, being smoother, of a lighter colour, 

 the concentric whorls a trifle narrower, than in a specimen of D. laciniata from Amboina, 

 of the same diameter, which I could compare with the specimen under cortsideration. The 

 operculum of a still smaller specimen from Banda, shows under the microscope about 16 whorls, 

 of which those near the nucleus are very narrow. The radula has about the same aspect, as 

 that of D. laciniata^ figured by Troschel (Gebiss der Schnecken, Vol. II, pi. 21, fig. 8); the 

 cusp of the rhachidian tooth is simple, while in a radula of D. laciniata from Amboina, each 

 side of the cusp seems to have a small, very pellucid denticle, which has not been mentioned 

 by Troschel, perhaps on account of its thin structure-, the body is higher in proportion to its 

 breadth, if compared with D. laciniata or atrata ; the fourth and fifth laterals (4, 5) are 

 considerably larger, than either in D. laciniata, or in its variety atrata, as figured by Troschel, 

 the length of the cusps surpassing much the diameter of the rhachidian tooth ; they have on their 

 base a secondary denticle, which is more distinct, than in my specimen of D. laciniata. Moreover 

 the primary cusps in D. laciniata are directed nearly horizontally, in spJiaertUa more oblique. 



Liotia Gray. 



I. Liotia varicosa Reeve. 



Reeve. Proc. Zool. Soc. Lond. 1843, p. 142 [Delphinula). 

 — — Conch. Ic. Vol. I, Delphinula, Sp. 12. 



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