340 



THE GENUS SCALA (KLEIN) HUMPHREY, AS REPRESENTED 



IN THE PERSIAN GULF, GULF OF OMAN, 



AND NORTH ARABIAN SEA, 



WITH DESCRIPTIONS OF NEW SPECIES. 



By JAMES COSMO MELVILL, M.A., F.L.S., and 

 ROBERT STANDEN (Assistant-Keeper, Manchester Museum). 



(Read before the Society, June loth, 1903). 



Since the publication of our Catalogue of the Gastropoda of the 

 Persian Gulf, Gulf of Oman, Mekran Coast, and that portion of the 

 Arabian Sea north of Panjim and Goa,^ as evidenced mainly by the 

 collections made by Mr. Frederick W. Townsend, of the Indo-European 

 Telegraph Service, we have received, and in part fully worked out, 

 several additional consignments from him, these including some siftings 

 of shell-sand and mud, dredged at a depth of from 140 to 160 fathoms, 

 in two or three prolific localities in the Gulf of Oman, the results, as 

 far at all events as concerns the Wentletraps, being embodied in this 

 paper, and swelling the number of Scalre reported from this region to 

 nearly fifty species. Mostly minute, they are, in our opinion, adult in 

 the vast majority of instances, and give another proof of the exceed- 

 ing wealth of the abyssal molluscan fauna. Amongst the sixteen 

 species now described we would especially mention Scala amathiisia, 

 S. calidea, S. deifica, S. emilice, S. laidlaivi, S. rissoinceforinis, S. toivn- 

 seudi, and S. continens, as possessing much beauty of form and sculp- 

 ture, though all needing a lens of some power to demonstrate this. 



Other families, such as the' Pleiirotomidce, possess an equal share of 

 interesting and hitherto unrecorded forms ; of these we shall shortly 

 hope to publish an account. 



Our best thanks are due to Mr. E. R. Sykes, Mr. W. Neville Sturt, 

 Mr. G. B. Sowerby, and above all to Mr. Edgar Smith, of the British 

 Museum, for aid and counsel. 



T^ * * -X- * 



For the use of the term Scala (Klein) Humphrey, 1797, in opposi- 

 tion to the till lately generally received and more familiar Scalaria 

 Lam., we would refer to the lengthy and exhaustive comments of Prof 

 W. H. Dall," of Washington, on the subject. He argues that by the 

 strict law of priority Cychstoiiia Lam., 1799, non 1801, nee 1804, 

 should be used, but as this would be so confusing, and by this -action 

 the next prior name Scalaria Lam., 1801, would be rendered unten- 

 able, Scala, as first proposed, unbinomiably, however, by Klein, in 

 1753, and then adopted by another unbinomial author, Humphrey, 

 in the Catalogue of the "Museum Calonnianum," may, for the sake of 



1 Proc. Zool. Soc, vol. ii. (1901), pp. 327-460, pi. .\xi,-x.\iv. 



2 £>'«//. 3/us. Contp. Zool. (Harvard College), xviii., no. 29, part ii., pp. 209-307. 



