"PLATE 13. 



Low-power Photomicrography. 



DOG FLI-A x 40 



Objective Zeiss Micro-planar. 25 mm. 



Condenser .. Watson's Universal, back combination. 



Screen Wratten's B and G (yellow-green), 5100-6000. 



Illuminarit ... Liliput arc 4 amps. 



Aux. Condenser Biconvex lens, parallel light. 



Plate Imperial N.F. 



Exposure ^ sec. 



.Photo. W. B. R To follow page 128. 



