IIEPORT ON THE LAMELLIBEANCHIATA. 149 



Circe ohliquissiina, n. sp. (I'l. 11. figs. (j-G/v). 



Testa parva, valdo oljliqua, sul)pyi-iformi.s, inajqiiilateralis, antice producta, subluuu- 

 lata, crassiuscula, albida, subdiapliaua, conceiitricu fortitcr costata et sulcata. Umbones 

 promineutes, subacuti. Cardo crassus. Deutes iii valva dextra tres ; duo postici sub- 

 aequales, anticus subobsoletus. Sulcus lateralis anticus latus, profundus. Ligamentum 

 internum, elongatum, pone dentem postremum situm. 



Tliis shell is remarkably ol)lique, very inequilateral, the anterior cud being much 

 greater than the posterior. It is produced in front, pyriforra, very strongly concentrically 

 grooved and ridged, the ridges being continued to the margins. In front; they are not 

 interrupted by a decided groove, but merely crossed by a slight depression marking off an 

 ill-defined lunule. The sulci are unequal, every alternate or third one being deeper and 

 l)r()ader than those intervening. The colour is white, the texture subdiaphanous, and the 

 surface somewhat glossy. The beaks are rather prominent, moderately acute, and 

 directed somewhat towards the front. The hinge is strong for so small a shell, and 

 consists of three cardinal teeth in the rioht valve. Of these the central is the largest 

 and parallel witli the hinder one, which forms the inner boundary of the ligamental pit. 

 The front tooth in the single valve under examination is subobsolete, and forms as it were 

 the upper extremity of the inner raised edge of the lateral dental groove. The ligament 

 is oblique, parallel with and located within the posterior dorsal margin. The interior is 

 glossy, and, owing to the transparency of the shell, exhibits the concentric sculpture of 

 the exterior. The muscular scars and impression of the mantle are too indistinct for 

 description. 



Length 4 mm., height 3|-, diameter about 2. 



Habitat. — Station 186, off AVednesday Island, North Australia, at a depth of 8 

 fathoms ; coral sand. 



This remarkable little shell is peculiar on account of the obliquity of its growth, and 

 the strong character of the concentric sculpture. It is quite unlike any other species of 

 the genus. 



Subfamily DosiNiix.^. 

 Dosinia, Scopoli. 

 Dosinia deshayesii, A. Adams (PL I. figs. 1-le). 



Dosinia deshayesii, A. Adams, Proc. Zool. Soc. Lond., 1855, p. 223. 

 Dosinia deshayesii, Rdmer, Monog. Dosinia, p. 55. 



Habitat. — Station 187, near Cape York, North Australia, at a depth of 6 fathoms 

 (Challenger) ; North Australia (Mus. Cuming) ; Prince of Wales Channel, Torres Strait, 

 in 5 to 7 fathoms (Dr. Coppinger of H.^M.S. " Alert "). 



