REPORT OF NATIOl^AL MUSEUM, 1923. 69 



should be made on the collection. Doctor Dall has completed the 

 manuscript, with the exception of the illustrations of the new 

 species. Dredgings by the Albatross off the east coast of Florida in 

 1885 and 1886 obtained a certain quantity of bottom material con- 

 taining numerous minute shells. These were segregated and 

 mounted for study by Doctor Dall and studied in the intervals of 

 other work. During the present fiscal year Doctor Dall undertook 

 the complete examination of the material, which comprised about 

 400 deep-sea species. The Dentalia had been worked up by Mr. 

 Henderson but the remainder were unexamined. The manuscript 

 has been completed except for certain comparisons. During the first 

 half of the fiscal year, John B. Henderson, a Kegent of the Smith- 

 sonian Institution, as in former years was an arduous, voluntary 

 worker upon the East Coast collections. Tlie major portion of 

 his time during the year was devoted to the preparation of a mono- 

 graph on the Turritidae of the Western Atlantic and continued 

 work begun in the past on a monograph of the Antillean land and 

 fresh-water mollusks, a list of the mollusks collected by the Bar- 

 bados-Antigua Expedition of the State University of Iowa and 

 work on the mollusk fauna of the vicinity of Beaufort, N. C. The 

 last problem was a cooperative study by Mr. Henderson and Dr. 

 Bartsch. Mr. Henderson unselfishly devoted considerable of his 

 time that might otherwise have been used for research to the routine 

 work of identifying East Coast material for outside correspondents. 

 His lamented death has deprived this division of an earnest, loyal, 

 and generous worker. Dr. Paul Bartsch, curator of mollusks, has 

 found the time consumed by answering routine questions and identi- 

 fying speciments to be increasing steadily. The economic impor- 

 tance of the mollusks is becoming more manifest each year. Apart 

 from their value as one of the most important food supplies, it is 

 only necessary to touch upon the shipworm problem, and their in- 

 creasing importance in their relationship to public health the world 

 over, as many of these forms serve as intermediate host in the com- 

 plicated life history of Trematode worms. Calls for identification of 

 material have come in not only from our own health offices and 

 schools of public health, but likewise from many other countries. 

 This means a necessary revision of the intermediate hosts in ques- 

 tion and incidentally the preparation of card catalogues of the vari- 

 ous species involved, in order to determine their relationship and dis- 

 tribution. The genus Planorbis^ one of importance in this connec- 

 tion, has required no less than 2,000 cards to permit of an intelligent 

 handling of the systematic problem. The greater part of Doctor 

 Bartsch's time available for research has been given to the mono- 

 graphing of the mollusks of the Mazatlanic faunal area. When 



