EAST AMERICAN SCAPHOPOD MOLLUSKS. 3 



of his methods Doctor Wiitson set an entirely new pace in systematic 

 work. The additions to the western Atlantic Scaphopocls therein 

 made, including his own new species and those of others regarded 

 by him as American as well as European, are as follows: 



DfjitaUum capillosum Jeffreys 

 (1876). 



Dentalium entalis orthrum Wat- 

 son. 



Dentalium circumcinctum Watson. 



DentaliuTn compressum Watson. 



Dentalium suhterjlssum Jeffreys 

 (1877). 



Dentalium didymum Watson. 



Dentalium ensiculus Jeffreys 

 (1877). 



Siphonodentalium platamodes 

 Watson. 



SiphcnodentaliuTn tytthum Wat- 

 son. 



SipJionodentalium tetraschistum 

 Watson. 



Cadulus vulpidens Watson. 



Cadulus rastridens Watson. 



Cadulus sauridens Watson. 



Cadulus curtus Watson. 



Cadulus curtus conf/ruens Watson . 



Cadulus curtus ohesus Watson. 



Cadulus exiguus Watson. 



Cadulus ampullaceus Watson. 



The Challenger was by no means the first to use the dredge in 

 American waters. The United States Coast Survey steamers Corwin 

 in 1867, the Bihh in 1868-9, the Hassler in 1871-2, the BacJic in 1872, 

 all made marine explorations with the dredge in connection wath other 

 oceanographic work in the Gulf of Mexico, the Straits of Florida, off 

 Yucatan, in the Caribbean, and in the Atlantic off Brazil. The 

 names of Count Pourtales, Louis Agassiz, and William Stimpson are 

 connected with these vessels but the amount of Scaphopod material 

 derived from their dredgings appears not to have been great. In 

 the case of the Bibh, which, under the direction of Pourtales, worked 

 in the exceedingly rich region off the Florida Keys, it is likely that a 

 fine lot of mollusks would have been added to the Government collec- 

 tions had it not been for their destruction in the great Chicago fire 

 while in the possession of William Stimpson, to whom they had been 

 given for report. 



It is to the Coast Survey steamer Blalce, during her three cruises 

 (1877-1880) in the Gulf of Mexico and Antillean waters, that are due 

 the largest and most important additions to our knowledge of the 

 American Scaphopod a. Under the able direction of Alexander 

 Agassiz and the command of officers, who fortunately took a keen 

 interest in the work, an exceptionally large amount of material was 

 obtained from many stations and from depths ranging from a few 

 fathoms to the ocean floor. Dr. William H. Dall, with his usual 

 thoroughness, reported upon this great collection of mollusks in two 

 Bulletins of the Museum of Comparative Zoology of the years 1881 

 and 1889. There appeared by far the most important as well as the 



