1522 



Journal of Applied Microscopy 



Fig. 6. — Nest-hole of Chickadees appropriated by House Wrens. Front view of circular 



entrance, showing the female approaching it with niotli miller. No screen was 



used here, but the foliage background was cut out of the picture. 



ond," the maximum time usually allowable, is too weak for successful printing 

 even after the intensifying process has been used. 



The most satisfactory small lens with which I have worked is the Zeiss 



Fif,. 7. — The same nest turned through an angle of cjo", with white cloth screen at back. 

 .Stump removed from tree, mounted on pivot, and protected by a fence of wire netting. 



