EEPORT OF NATIONAL MUSEUM, 1925 63 



made a joint survey of the rotifer fauna of Mount Desert Island, 

 and plan to continue these studies during the ensuing summer. 



Dr. W. H. Dall, honorary curator of moUusks, studied material 

 obtained by the Canadian Arctic expedition from the Arctic coast 

 of Alaska and Canada, and prepared a report to be published by 

 the Canadian Government. New species of mollusks from Florida 

 and Japan were studied and described. At the request of Yale 

 University, material dredged off the northeast coast of America 

 and on the Grand Banks was studied; the results will be published 

 in the American Journal of Science. A revision of the last American 

 species of Pecten, Plicatula, and Petricolaria was printed. A revi- 

 sion of the collection of east American Pelecypoda was completed. 

 The curator. Dr. Paul Bartsch, devoted some time to the prepara- 

 tion of a monograph of the Philippine mollusks of the family 

 Naninidae. The first volume on the larger members of this group is 

 completed, except for a few illustrations which are being prepared. 

 Work on cerions was continued and the curator is again under 

 great obligations to Thomas S. Creighton, of Blue Ridge Summit, 

 Pa., and Washington, D. C, for his volunteer services in measuring 

 and cataloging the forms added to the collection during the past 

 year. Strides were also made in the dissection of the hybrid Cerion 

 material. Sundry minor reports were prepared as indicated in the 

 bibliography. The assistant curator, William B. Marshall, described 

 and published on a number of new forms while descriptions of 

 others are in process of publication. Work on the pearly mussels 

 of the northern Mississippi Valley was continued and Mr. Marshall 

 hopes to finish this during the coming year. 



The curator of echinoderms, Austin H. Clark, has nearly finished 

 the text of part 3 of his monograph of recent crinoids. Of part 4, 

 which includes the discussion of stalked crinoids, the account of the 

 anatomy of the various types so far as the " soft parts " are con- 

 cerned, is complete, and the synonymies have mostly been worked 

 out. This part includes about 100 species as against about 600 

 in part 3. 



In the division of plants Dr. Frederick V. Coville, curator, con- 

 tinued studies in the breeding and propagation of blueberries {Vac- 

 cinium) and began similar studies of the gooseberries {Grossularia) . 

 Dr. J. N. Rose, associate curator, continued studies of the family 

 Caesalpinaceae, in collaboration with Dr. N. L. Britton, director of 

 the New York Botanical Garden, with a view to publishing a mono- 

 graph of the North American species of this family. Doctor Rose 

 also gave attention to the Crassulaceae and Cactaceae, in continuation 

 of earlier monographic studies. Dr. William R. Maxon, associate 

 curator, continued work on the ferns of tropical America, with 



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