98 EEPOET OF NATIONAL MUSEUM, 1920. 



genus Ai-nJca, under revision by Doctor Rydberg; 310 specimen?, 

 chiefly Indigofera, lent to the New York Botanical Garden for raoii >- 

 graphic study by Doctor Rydberg; 1,518 specimens of Scrophu- 

 lariceae, members of the genus Veronica, lent to the New York 

 Botanical Garden for monographic study by Dr. F. W. Pennell; and 

 255 specimens of Robinia, Coursetia, and related genera, lent to the 

 New York Botanical Garden for monographic study by Doctor Ryd- 

 berg. 



DISTRIBUTION AND EXCHANGE OF SPECIMENS. 



Duplicates distributed to schools, colleges, institutions, and indi- 

 viduals aggregated 1,874 specimens, of which 1,044 were in 6 sets of 

 174 mollusks, regularly prepared for this purpose, and one set of 91 

 fishes similarly prepared. 



During the early part of 1919 the associate curator of insects had 

 one of the preparators collect a considerable quantity of the seven- 

 teen-year cicada, then abundant, knowing that it does not occur in 

 many parts of the country. Applications for this material were re- 

 ceived from many colleges and specimens illustrating nymph, nymph 

 cases, and adults (100 specimens) were sent to eight. 



Exchanges to the number of 13,681 specimens were' arranged, 

 12,918 being botanical. Of the 763 zoological specimens 419 bird 

 skins from Costa Rica. Celebes, and the Philippines were sent to 

 the American Museum of Natural History, and 170 bird skins from 

 Celebes to the Museum of Comparative Zoology. The remainder 

 were disposed of in exchange with various institutions and indi- 

 viduals. The largest exchanges of plants were sent to the Botanical 

 Museum of the University at Copenhagen, Denmark, and the New 

 York Botanical Garden. A large number of sets of 500 and 300 

 specimens each ware disposed of to 17 different museums and botani- 

 cal gardens in this country and abroad. 



TOTAL NUMBER OF SPECIMENS IN DEPARTMENT OF BIOLOGY, INCLUDING NUMBER OP DUPLICATE 



SPECIMENS. 



The figures given below are not based upon actual counts, but 

 represent more or less accurate estimates made from time to time. 

 The total is probably approximately correct. It includes about 

 180,000 duplicates and superfluous specimens, of which a large num- 

 ber are available for distribution and exchanges. 



Duplicates have not been segregated in several of the divisions 

 because of lack of help, but especially because so comparativelv little 

 of the material has as yet been monographically worked over. It 

 should also be remarked that this census does not include the collec- 

 tions of mammals and birds in the custody of the Biological Survey. 



