128 



10. Lima {Li?natula) leptocarya Melvill. (Plate IV, figs. 7, 8). 



1898. Lima [Liniatula] leptocarya Melvill, Mem. Manchester Soc. XLII, p. 28, pi. II, fig. 2. 

 igo6. Lima [Liinattcla) leptocarya Melvill &Standen, Proc. Zool. Soc. London, p. 812, pi. LV, fig. 5. 

 1920. Lima [Limatnla) leptocarya Thiele, in Martini-Chemn. Conch.-Cab. (N. F.), VII {2 a), 

 Limidae, p. 49, pi. IX, fig. 18. 



I hâve compared the "Siboga" spécimens, which I assign to L. [L.) leptocarya^ with the 

 type of the species in the British. Muséum (Nat. Hist.), London, and can find no différence, 

 except that the "Siboga" spécimens are about twice the size of the type. The measurements 

 of the largest of the "Siboga" spécimens are: — length 9.4 mm.; height 14.9 mm.; thickness 

 (single valve) 4.5 mm. I figure a shell from the Persian Gulf. 



Distribution: — The type of the species came from a depth of 10 fathoms at Muscat 

 in the Persian Gulf, but later other spécimens were obtained in the Gulf of Oman at 60 fathoms. 



The "Siboga" material, consisting of odd valves, was collected at Sailus Ketjil, Paternoster 

 Islands (St. 37), Western entrance, Samau Strait (St. 59), Kambaragi Bay, Tanah Djampeah 

 (Stat. 64), Muaras Reef, inner side, east coast of Bornéo (St. 91) and St. 98 (6° 9' N., 120° 21' E., 

 350 mètres). 



11. Lima {Limahila) sibogai sp. nov. (Plate IV, figs. 9, 10 and Plate VIII, figs. 13, 14). 



I hâve not been able to refer a number of spécimens of the subgenus Liniatula dredged 

 from a depth of 1886 mètres from near Celebes to any previously described species, and believe that 

 it is new to science. The follovving is a description of this new species : — 



Species of a médium size, thin-shelled, translucent, greatly inflated, somewhat compressed 

 from side to side and having a médian ridge running from the umbones to the posterior margin ; 

 elongated-ovoid, somewhat asymmetrical as the anterior half is more convex than the posterior ; 

 upper angles distinct, marking off the narrow, subequal auricles ; umbones subcentral, distant, 

 pointed, incurved ; hinge-area comparatively narrow with a centrally situated triangular ligamental 

 pit; sculpture consisting of numerous low, thread-like radial ribs ; the latter are not so deeply 

 impressed but produce by intercrossing with the radial ones a regular reticulated sculptured surface ; 

 ventral margin sharp ; colour creamy white, inner surface shining. 



Measurements (in millimètres) 



Length 8.2 



Height 12.7 



Thickness 7.5 



Habitat: — L. {L.) sibogai was, as noted above, dredged from a depth of 1886 mètres 

 at St. 208 (5° 39' S., 122° 12' E.). 



Remarks : — This new species appears to be allied to L. {L.) simillima Thiele ^), but 

 is distinguished by its more arched and inflated shell, broader hinge-area, more pointed umbones 

 and sculpture. 



i) Thiele, J. — in Martini-Chemn. Conch.-Cab. (N. F.), VIII (2^), Limidae^ p. 54, pi. X, fig. i (1920). 



