184 The Spermatogenesis of Abraxas 



PLATE XXXIII. 



EXPLANATION OF FIGURES. 



All the figures except Fig. 21 were drawn with a Zeiss immersion apochromat. 3 mm. 

 N. A. 1-40, and Compens, Oc. 12. 



Fip. 21, a, 6 was drawn with a 12 mm. objective. 



Fig. 1. Spermatogonial mitoses. 



a. Equatorial plate in face ; about .54 chromosomes visible. 



b. iVIetaphase in side view. 



Figs. 2 — 9. First spermatocyte divisions, large "normal " type. 



Fig. 2. Early prophase: chromosomes on nuclear membrane. The nucleus extends 

 through more than one section : only those in one section are represented. 



Figs. 3 — 6. Equatorial plates in face. Fig. 3, wild grossulariata; Fig. 4, lacticolor; 

 Fig. 5, heterozygote. These three show 28 chromosomes. Fig. 6, heterozygote, 

 showing 29 chromosomes, probably owing to premature division of one. 



Fig. 7. Equatorial plate, side view. 



Figs. 8, 9. Early and late anaphases. 



Figs. 10 — 12. Second spermatocyte division, large "normal" type. 



Fig. 10. Equatorial plate, a. heterozygote. b. lacticolor. 



Fig. 11. Equatorial plate, side view. 



Fig. 12. Telophase. 



Figs. 13 — 19. Spermatocyte divisions, small irregular type. 



Fig. 13. Early prophase of first division ; the nucleus extends through about three 

 sections, one of which is represented. There were altogether over 50 chromosomes. 



Fig. 14. Later prophase, one section of nucleus. Altogether 18 double and 10 or more 

 single chromosomes were counted. 



Fig. 15. Equatorial plate of first division. 31 chromosomes appear to be present, pro- 

 bably owing to premature division. 



Fig. 16. Same stage, side view. 



Fig. 17. Anajjhase of first division, showing scattering of chromosomes. 



Figs. 18, 19. Second spermatocyte division, early and late anaphases. 



Fig. 20. Spermatids in process of conversion into spermatozoa. Reconstructions com- 

 bined from more than one section. 



a. (Above) large " normal " type ("Eupyrene," Meves). 



b. (Below) small abnormal type ("Apyrene," Meves). 



Fig. 21. (Drawn with i in. objective.) Bundles of nearl}' mature spermatozoa. 



a. (Above) normal ''Eupyrene." 



b. (Below) abnormal "Apyrene." 



