696 CLARENCE L. TURNER 
Fig. 3. Camera lucida drawings to show size relationships of cells during 
different periods. All figures except e and f represent outlines of nuclei and all 
are drawn to the same scale with an X8\ocular and 1.9 mm. oil immersion lens. 
A. Germ cells in cord outside of testis (May 5). B. Germ cells at ‘periphery of 
testis (May 5). C. Germ cells during period of growth and proliferation (July 
3). D. Germ cells during latter part of period of growth and proliferation. 
Maximum size of cells shown (August 5). E. Outline drawings illustrating 
comparative size of largest and smallest cells in a lobule, also volumetric rela- 
tions of cytoplasm, nucleus and plasmosome; cyt., cytoplasm; n., nucleus; pl., 
plasmosome. F. Drawing illustrating size relations during : transformation of 
germ cells into spermatogonia; vac., clear vacuole of liquid surrounding trans- 
forming cell; cyt., cytoplasm; n., nucleus. G. Group of spermatogonia. H. 
Group of primary spermatocytes. I. Group of secondary spermatocytes. J. 
Group of spermatids. K. Group of spermatozoa. 
