CYTOPLASMIC INCLUSIONS OP THU GKRM-CELLS. 611 
Fig. 33. — Prophase showing astral body (.4.$.), which will give rise to 
part of the spindle. Mitochondria at this stage often rod-like. Neben- 
kern has lost its original disposition. 
Fig. 34. — First maturation division metaphase, showing shape of 
mitochondria and general difficulty of detecting Nebenkern rods. 
Fig. 35. — Spermatid with small mitochondria and straight or slightly 
curved Nebenkern rods. Nucleoli few in number. (For P.N.A. see 
Addendum A.) 
Fig. 36. — Spermatid of same generation. 
Fig. 37. — Later spermatid showing collapse of Nebenken structure. 
Fig. 38. — Probable nurse-cell showing nucleus and cytoplasmic bodies. 
No yolk disclets remain (or have been formed). The exact history of this 
cell is difficult to make out (see p. 591). 
Fig. 39. — Spermatogonial division with few large mitochondria. 
Compare PI. 32, fig. 28. 
Fig. 40. — Spermatid with ring-like Nebenkern rods and large mito- 
chondria. 
PLATE 34. 
Figs. 41, 42, 43, 44, 45, and 46. x 2000. 
Figs. 40 to 45 stages in the formation of the sperm. 
Fig. 46. — Sperm from smear drawn to scale of the foregoing figures 
(S-). 
Fig. 47. — Spermatid X 2000, showing manner in which axial filament 
grows in cramped quarters. The micromitochondria keep their definite 
position. 
Fig. 48. — Spermatid nuclei X 2000, showing variations found in 
chromatin nucleoli. These hold good without much variation for every 
nucleus in the bunch of spermatids. 
Fig. 49. — Male progerminative cell (primary spermatogonium) of the 
generation drawn in Text-fig. 3, ii, S.P.P. X 4250. 
