PLATE 15. 



Low-power Photomicrography. 



MEDIAN LONGITUDINAL SECTION OF A NEWLY-BORN MOUSE x 6 



Stained in hulk in borax carmine, counterstained in aniline blue 

 and picric acid. 



Objective Aldis micro-anastigmat, 3". F. 7. 



Ocular None. 



Condenser ... A double convex lens, 5cm. in diam. and 

 7 cm. focus placed immediately below the 

 microscope stage. 

 Camera Ext. ... 25. 5". 



Screen None. 



Plate Barnet isochromatic. 



Illurninanl ... Petrol vapour. 



Exposure 2 sec. 



Developer ... Metol-quinol. 



An example of low-power photomicrography of a large transparent 

 object, involving the use of an objective of great covering power and 

 .a condenser of wide diameter. The procedure is described on page 137. 



Photos. H. L. H. r/o follow page 136. 



