172 BULLETIN OF THE 



In 1881, however, 1 was able to prepare preliminary descriptions of 

 Bome of the more striking novelties (BuU. Mus. Comp. Zool., Vol. IX. 

 No. 2,* pp. 33-144) and enumerate some of the more remarkable forms 

 in the collection which had been described already. The dredgings of 

 the U. S. Fish Commission having produced a number of deep-water 

 species of limpets and chitons, — which were generously submitted to 

 me for study by Prof A. E. Verrill in charge of that material, — the 

 investigation was facilitated by the possession of the Blake collection, and 

 the study of the whole brought about the publication, in 1882, f of some 

 extremely interesting facts in regard to these groups of mollusks. 



Lastly, the investigation of the literature necessary for this work, and 

 for the determination of the Tertiary fossils of the Southeastern United 

 States, culminated in the preparation, under my supervision, of a general 

 index to the species reported from the coast and islands of the region 

 between Cape Hatteras, North Carolina, and Cape San Eoque at the 

 northeastern extremity of South America, including the Bermudas and 

 West Indies. This is the first attempt to bring together the names of 

 the alleged species said to inhabit this region, though there have been 

 a number of excellent local catalogues. The list was found so useful for 

 both biological and paleontological purposes, that it was printed by the 

 U. S. Geological Survey as one of its Bulletins. t A short article on the 

 characters of Dimya, based on the study of the soft parts, first collected 

 by the Blake expedition, was printed in Science (No. 2, Feb. IG, 1882, 

 p. 51). 



* This Bulletin was first published in signatures, distributed as soon as printed 

 to those most interested, as follows : pp. 33-48, July 12, 1881 ; pp. 49-64, Aug. 12, 

 1881 ; pp. 65-80, Aug. 25, 1881 ; pp. 81-96, Sept. 26, 1881 ; pp. 97-112, Oct. 31, 1881 ; 

 pp. 113-128, Nov. 26, 1881 ; and the remaining pages and index, Dec. 5, 1881. By 

 the great kindness of the Rev. R. Boog Watson, who supplied nae promptly with 

 his preliminary descriptions of the Challenger gastropods, of Dr. Paul Fischer, and 

 of the late Drs.^Thomas Davidson and J. Gwyn Jeffreys, who, working on deep- 

 sea material, were equally considerate, I was enabled to complete this preliminary 

 work without clashing in the matter of priority; all the descriptions of particular 

 groups in the Bulletin alluded to being either intentionally subsequent or clearly 

 prior to the work of the above-mentioned gentlemen on the same groups. It need 

 hardly be said, that, when they led the way I was greatly the gainer from the ac- 

 knowledged experience and ability with which their tasks were performed, and 

 which greatly lessened my own labors. 



t " On certain Limpets and Chitons from the deep Waters off the Eastern Coast 

 of the United States, by W. H. Dall." Proc. U. S. Nat Mus., Vol. IV. pp. 400- 

 414, April, 1882. 



t Bulletin U. S. Geological Survey, No. 24, 336 pp., 8vo. Washington, Govern- 

 ment Printing Office, 1885. 



