166 Naturalist at Large 



the hides of the larger forms and hang them up on rods 

 in a large room which we keep sterilized against moths 

 and other pests. But generally speaking, standard trays are 

 used for fossils, alcoholic material, and all of the myriad 

 types of material which are gathered in the Museum pri- 

 marily to aid investigators and not to instruct the public. 



The trays measure i8 X 27/2 X 372 inches, except those 

 in the Mollusks Department, where they use a good many 

 thousand. Theirs are only an inch deep on account of the 

 small size of most of the material involved. These trays 

 are contained in tall, narrow, glass-door cupboards, placed 

 side by side, each containing twenty runners spaced so that 

 the trays slide in and out. For very heavy objects we 

 simply put the tray in upside down and thus it becomes a 

 shelf. Where tall jars of fish or reptiles are stored, we have 

 to use a tray to each four or five or six spaces. Of course 

 no system is universally convenient, but our trays, now 

 that we use galvanized-iron runs to support them, slide 

 in and out quite easily even when loaded with very heavy 

 material. We use about 500 new trays a year and estimate 

 that at the present time there are 50,000 in use in the 

 building. 



It is idle to speculate on the number of specimens, for 

 it would be sheer guesswork. Mr. Nathan Banks, for in- 

 stance, estimates that there are three and a half million 

 insects in the collection and knows that there are at least 

 30,000 types — that is, specimens from wliich new species 

 have been described. This number has been definitely lo- 

 cated; no doubt there are several hundred more in the 

 collection not as yet found. Our insects are gradually all 

 being worked into standard, glass-topped, airtight trays 



