PLATE 27. 



Stereoscopic Photomicrography. 



GROUP OF INSECT EGGS MOUNTED AS OPAQUE OBJECT x 14 



Objective Crouch 2". Stopped down. 



Ocular None. 



Illuminanl ... Incandescent gas. 



Condenser ... Bull's-eye, projecting convergent beam of light 

 on to the object. 



Plate Imperial Special Sensitive. 



Exposure omiii. 



Developer . . Pyro-soda. 



The method employed is as described on page 193, involving a 

 slight movement of the preparation on the stage, and two exposures 

 on a half-plate. 



Photo. W. B. R. To follow Plate 26 and page 192. 



