14 BOTANICAL GAZETTE [JULY 
Syncephalis cornu Van Tieghem. 
Fig. 17. Zygospore with sterile outgrowths. J. oc. 2. 
Syncephalis nodosa Van Tieghem. 
Fic. 18. Gametes (x, y) seen from above in process of conjugation. The 
gamete x separated from the hypha which bears it by a septum (2). J. oc. 2. 
Fic. 19. The same. A dieing has begun to bud from the gamete (+) 
just above the septum (z). J. oc. 
Fic. 20. Conjugating filaments viewed laterally, the inner shown by 
dotted lines through the outer. Letters as in previous figures. The 
spiral filament which bears the gamete (x) producing sterile outgrowths. J. 
Ot. 2. 
Fic. 21. Two similar conjugating hyphe, the inner not indicated by 
dotted lines. 
Fi1G. 21a. Mature zygospore seen in optical section, its connection with 
the gamete (x) still attached. J. oc. 2 
Syncephalis tenuts Thaxter. 
Fic. 22. General habit of mature fertile hypha, about one-sixth of its 
length indicated by dotted lines. D. oc. 4. 
Fic. 23. Terminal portion of fertile hypha showing immature sporan- 
gial filaments, the terminal half of which is just beginning-to form. D. oc. 4. 
Fic. 24. Fertile head from which the basal halves of the sporangial fila- 
ments have been produced, D. oc. 4. 
Fic. 25. Mature head of variety with larger spores. D. oc. 4. 
FIGs. 26-29. Successive stages in development of sporangial filament. J. 
Fic. 30. Separated spores of elongate type. J. oc. 2. 
FIG. 31. Spore of large spored variety. J. oc. 2. 
Syncephalis (Microcephalis) pycnosperma Thaxter. 
Fic. 32. General habit of nearly mature fertile hypha. D. oc. 4. 
F1G. 33. Terminal portion of fertile hypha showing numerous secondary 
sporophores from which the sporangial filaments are in sg iat of formation. 
ae. 3: 
Fic. 34. Mature head seen in optical section showing secondary sporo- 
phores, one of them furcate, from most of which the spores have fallen. J. 
OC; 25 
Fic. 35. Young sporangial filament showing two intermediary zones, the 
lower not completed, the upper nearly complete; 4, the separation disk; % : 
