REPORT ON THE LAMELLIBRANCHIATA. 33 



Occasion lias already becu taken to remark upuu the great similarity existing between 

 two species of this genus, the one {Curhula siiJcata) from the shores of Western Africa, 

 the other {Corhula tunicoAa) from Amboina, the Philippines, North and East Australia. 

 In the present instance I have to repeat tlie record of the existence of the very same 

 shell from all these localities, with the exception of East Australia. A single example 

 dredged by Captain Knocker, R.N., at Whydah, on the Dahomey shore, was referred to 

 this species by myself in 1871. I have again most carefully examined it, and see no reason 

 for altering that location. The apices of the umbones are of the same smooth porcel- 

 lanous whiteness, bordered in front with a pinkish stain as in eastern specimens, the 

 concentric ribbing is identical, the colour of the interior the same, and the hinge and 

 muscular scars correspond in every respect. 



If there were more specimens for examination, it is possible some distinguishing 

 feature might present itself, but at present I feel certain of the identity of these shells 

 from such widely remote and distinct zoological provinces. 



Corhula pMlippii, n. sp. (PI. VIII. figs. 4-46). 



Testa parva, valde insequivalvis, insequilateralis, triangulariter ovata, alba, valva 

 sinistra epidermide fibrosa prope marginem induta. Valvse crassiusculse, diverse sculptae. 

 Valva dextra convexa, postice breviter rostrata, ad extremitatem truncata, obtuse 

 bicarinata, costellis rotundatis, crassiusculis, concentricis, prope carinam anteriorem fere 

 evanidis, instructa. Valva sinistra longe minor, incrementi lineis striata, liris paucis 

 radiantibus ornata. Umbones valde prominentes, involuti, nivei, l?evigati. Linea 

 cardinis utrinque declivis, rectiuscula, fusco tincta. 



This compact little species is very inequivalve, rather convex, somewhat inequilateral, 

 triangularly ovate with the umbones well raised. The anterior end is sharply rounded, the 

 posterior subrostrate, shortly and slightly obliquely truncate, the lower margin being well 

 curved in front and at the middle, and very faintly incurved behind near the lower angle 

 of the rostrum. It is w^hite with the exception of a slight tinge of brown upon the hinge- 

 margin, chiefly behind the beaks, and the left valve is clothed more or less, principally 

 towards the lower outline, with a yellowish fibrous epidermis. The right valve, which is 

 far the larger, has an obtuse ridge running from the apex obliquely to the lower end of 

 the hinder truncation, marking off" a definite and somewhat concave posterior area, and 

 within this, close to the dorsal margin, it has a second less noticeable rounded carina. 

 Its sculpture consists of rounded concentric ridges which gradually tliicken as the shell 

 increases. They are numerous, broader than the intervening grooves, attenuated (in 

 some instances obsolete) anteriorly, and become mere strise between the radiating cariu;e 

 behind. The left valve merely exhibits fine concentric lines of growth and a few (about 



(ZOOL. CHALL. EXP. PART .XXXV. — 1885.) Mm 5 



