460 
J. BRONTE GATENBY. 
Fig. 2. — Spermatogonial metaphase from side. On the left are th& 
mitochondria and on the right are two equal-sized bodies which are 
the micromitosomata. The side of the cell drawn in more thickly is 
the morula- wall. 
Fig. 3. — Spermatogonial anaphase from Flemming with reduced 
acetic acid fixation. On right is in the lower cell a micromitosome 
and on left are mitochondria, and in the upper cell the other micro- 
mitosome. Between the cell are three small thickenings forming an 
equatorial plate. 
Fig. 4. — Contraction figure stage showing micromitosome (M.), centro- 
some ( C .), mitochondria (M.D.), and the “ reste fusorial,” or spindle 
bridge ( S.B ). 
Fig. 5. — Young spermatocyte in growth stage showing mitochon- 
drial cloud, micromitosome, and centrosome which has come to surface 
of the cell. 
Fig. 6. — Later stage, showing mitochondria, micromitosome, and 
centrosome which has divided and from which four flagella begin to 
appear. Cell processes (C.P.) appear. 
Fig. 7. — Spermatocyte with mitochondria better defined, centrosomes 
separated, and filaments longer. In some parts (M.D.Y.) the mito- 
chondria are larger than in others ( M.D.X. ). 
Fig. 8. — Almost at end of growth-period, showing well-defined mito- 
chondria forming a crust around the nucleus. Micromitosome near 
top of figure. Acroblasts (A.B.) with concave surfaces to nucleus. 
Fig. 9. — First maturation division showing arrangement of mito- 
chondria. Micromitosomata near centrosomes. Acroblasts near poles 
of spindle. 
Fig. 10. — First maturation anaphase, showing micromitosomata (M.), 
equatorial plate thickenings {E.P.), and mitochondria. Right centro- 
some dividing. Acroblasts orientated in the characteristic manner. 
Fig. 11. — Equatorial view of first maturation division spindle show- 
ing precocious running together of mitochondria (F.) and the twenty- 
eight chromosomes. 
Fig. 12. — Spermatid just after second maturation division, showing 
mitochondria, micromitosome ( M .) and centrosome, which is just 
dividing. One centrosome keeps its connection with the axial filament. 
At A.B. are several acroblasts. 
Fig. 13. — Spermatid at a little later stage ; only one centrosome and 
five acroblasts could be found. 
Fig. 14. — Spermatid showing the incipient formation of the macro- 
mitosome (nebenkern); on the right a continuous chord is already 
