About 21,300 insects and their allies, collected by Associate Curator 

 Dybas on various field trips in the United States during the last 

 six years, were also accessioned. 



Mollusks were added to the collections at such a rate that the 

 size of our collections was about doubled this year. The additions 

 were acquired through purchases, gifts, and exchanges. Some of the 

 additions were: more than 300,000 specimens representing about 

 18,000 species, a worldwide collection purchased from the estate of 

 the late Charles D. Nelson of Grand Rapids, Michigan; about 75,000 

 specimens of nonmarine shells from the middlewestern United 

 States, collected by the late A. C. Billups of Lawrenceburg, Indiana 

 (purchase); a very complete synoptic set of Malayan and Indo- 

 nesian nonmarine shells collected by Dr. F. F. Laidlaw of England 

 (purchase); and a set of more than 8,000 Libya desert snails pur- 

 chased from Dr. Rolf Brandt of Libya. An exceptionally fine series 

 of cone and cowry shells was donated by Dr. Jeanne S. Schwengel of 

 Scarsdale, New York, and a magnificent collection of some 7,000 

 marine shells, many of which are large and exceptionally beautiful 

 in color and form, was given by the estate of the late Dr. C. W. 

 Yarrington of Gary, Indiana (see pages 22 and 76). 



Care of the Collections— Zoology 



Before a specimen is incorporated into our study collection, in no 

 matter what group, the labeling must be checked and, where neces- 

 sary, labels conforming to our standards added. This labeling 

 enables us to tell whence any specimen came and when and by 

 whom it was collected. We also hke to have the name of the animal 

 written on the label, so that anyone can tell what the animal is, and 

 the name of the Museum, indicating our ownership. 



Problems of labeling vary, as one might expect when such diverse 

 objects as tiny seashells, elephant skins, leafhoppers, snakes, and 

 fishes are handled and when some of the specimens are preserved wet, 

 in pickle, others are dried in one piece, and yet others, like dis- 

 articulated skeletons, are composed of many small parts. In no 

 group does this labeling require more painstaking care than in 

 insects. The pin that holds the specimen may also carry four or even 

 more labels (see page 75). 



This labeling as well as other duties in the care of the collections 

 are routine: poisoning to prevent ravages by insect pests, making 

 sure that the preservative on each pickled specimen is adequate, and 

 rearranging the collections to include new material. During the year 



71 



