163 



This material was fixed with P/,, chromic acid and stained 

 with gentian violet and aniline safranine. The coloring thus 

 obtained was beautifully clear, and the blepharoplast stained 

 with extraordinary sharpness. The spermatozoids of 0. pendulum 

 are even larger than those of 0. moluccanum, and a very 

 satisfactory series of these was prepared, which has made 

 it possible to study practically all of the stages ot develop- 

 ment. In the study of the spermatozoids in 0. peruhduni the 

 material was fixed with weak Flemming's solution and also 

 P/o chromic acid. Both of these reagents fixed the material 

 satisfactorily. The nucleus was rather better stained in the 

 chromic acid preparations, as there was a tendency to over- 

 stain in the other material, but the blepharoplast and cilia 

 were much clearer in the material fixed with the Flemming 

 solution. In all cases the same double stain was employed. 



If the sperm cells are examined previous to the final division 

 to form the spermatocytes (Figs. 79, 84) the nucleus will 

 usually show a small but distinct nucleolus and a dense reti- 

 culum. The whole stains strongly with safranine. The cytoplasm 

 is fairly dense, with granules of various kinds in it. In the 

 material fixed with Flemming's solution there are often small 

 black specks, perhaps fatty bodies, which sometimes interfere 

 somewhat with the study of the cytoplasm. In well stained 

 sections the blepharoplasts may be seen as two small rounded 

 bodies (b) lying near the nucleus. Several cases of the final 

 nuclear divisions were met with, but all of these were in 

 material fixed with chromic acid, and the blepharoplasts were 

 not very well differentiated (Fig. 85). The nuclear spindle is 

 very distinct, and the nuclear segments extraordinarily numerous. 

 Indeed, it was quite impossible to determine their number, 

 but the figures (85, 86) will show the very large nuclear plate. 

 The latter was often sectioned transversely so that the whole 

 number of segments could be seen (Fig. 86). The numl)er of 

 chromosomes is evidently much greater than in the nuclei of 

 the younger antheridicil cells. (Compare for example Figs. 73, 

 85). In the young spermatocyte (Fig. 87) the nucleus shows a 



