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Show 1881.] MR. E. A. SMITH ON THE GENUS GOULDIA. 489 8. On the Genus Gouldia of C. B. Adams, and on a new Species of Crassalella. By E D G A R A. S M I T H. [Received March 15, 1881.] Special attention having been called to the name Gouldia in tbe volume of the Society's 'Proceedings' for 1879 (p. 131) by Mr. W . H. Dall, in a communication entitled " O n the Use of the generic name Gouldia in Zoology," I beg to present to the Society a few observations on the Molluscan group bearing this designation. Having recently had occasion to examine some of the shells which have been described under that name, I find that it is untenable; and therefore the genus Gouldia of Bonaparte is left free for adoption by ornithologists. The types of Adams's genus were two species from the West Indies, G. cerina and G. parva. Of these the former proves to be a species of Circe, and the latter a small Crassatella. This (parva), says Carpenter (Mazatlan Cat. p. 82), "bears a general resemblance to Circe minima." This, however, must be erroneous, probably a lapsus calami. He states that he examined specimens of G, parva in Mr. Cuming's collection ; these, however, I cannot now find; and it appears to me that it was, in all probability, the G. cerina which he had before him, specimens of which are preserved in the Cumingian collection. The latter does "bear a general resemblance to Circe minima," whilst the description of G. parva in no way accords with it, but rather characterizes one of the Crassatelloid species found in the West Indies, which have been assigned to Gouldia. C. B. Adams's description runs thus:-"Testa Astarte affini, sed dente laterali remota anteriore in utraque valva instruct a ; pallii impressione vix vel haud sinuata." These characters do not well apply to the first of his species, G. cerina ; for that is very unlike an Astarte, lacking the epidermis so characteristic of that group, and having coloured markings, which, with one exception, are altogether absent in the genus referred to. I am therefore inclined to believe that the Astartoid resemblance referred to the second species, G. parva, his description being applicable to Astarte, and the shell which I refer to it certainly not unlike that genus, being compressed and strongly concentrically ridged and sulcate. Adams's generic diagnosis (Proc. Bost. Soc. Nat. Hist., 1845, vol. ii. p. 9) makes no mention of the hinge-ligament. In his G. cerina, however, it is semiexternal, as in Circe, whilst in his G. parva and G. pacifica it is internal, as in Crassatella. This has been pointed out by Carpenter in 1863, in his Supplementary Report on the Mollusca of the West Coast of North America, p. 544, where he observes, "It appears that Gouldia (Thetis, C. B. Ad. olim, non Sowerby, nee H. and A. Ad.) is congeneric with " Circe" minima, not with the Astartids. Prof. Adams's fresh specimens of his G. pacifica prove to have the crassatelloid internal ~PROC. ZOOL. Soc-1881, No. XXXII. 32 |