102 ALBERT FRANCIS BLAKESLEE. 



PLATE III. 



FIGS. 25-28. "Imperfect hybridizations" between Mucor V. ( ) and Zygo- 

 rhynchus heterogamus ( ). Fig. 25 from living material. Figs. 26-28, gamete 

 formation. 



FIG. 29. "Imperfect hybridization" between Zygorhynchus Vuillemini var. 

 agamus and Zygorhynchus helerogamus showing formation of azygospore from 

 gamete of former species. 



FIGS. 30-32. "Imperfect hybridizations" between Mucor V. (+) and Zygo- 

 rhynchus Vuillemini var. agamus. Fig. 30, progamete formation. Fig. 31 drawn 

 at 9.55 P.M., Dec. 20. Fig. 32 drawn at 10.45 A.M., Dec. 21. 



FIG. 33. Apposed azygospores of Absidia spinosa developed from male and 

 female gametes, m and / apparently represent respectively male and female 

 progametes which have been pulled apart in mounting. 



