ZYGOMYCETES 



115 



at the ends of hyphae or of their branches (Fig. 69, 1-2). On their 

 surfaces they form very thin, rapidly tapering processes which later, 

 because of the enlargement of the copulation branch, are shoved aside 

 or toward the base. These are probably the fundaments of the hyphae 

 which surround the zygospores at maturity. 



Fig. 69. — Endogone lactiflua. 1. Young copulation branches in contact. 2. Single 

 copulation branch. 3. Two gametangia with numerous peripheral nuclei. 4. Large 

 central nucleus in the female copulation branch. 5. Formation of copulation opening. 

 6. Nuclear migration. 7. Formation of hyphal sheath around zygote. 8. Zygote still 

 connected with gametangia. Endogone incrassata. 9. Section of sporocarp with peridium 

 and gleba. 1,2 X 400; 3 to 5, 7 X 630; 8 X 370; 9 X 10; after Bucholtz, 1912, and Thaxter, 

 1922.) 



The female copulation branch is somewhat larger and bent at the 

 base. The copulation branches press together and bend around so that 

 the male is surrounded by the female. Their content is granular and 

 multinucleate. The nuclei are arranged peripherally (Fig. 69, 3) and 

 undergo a simultaneous division, after which, in the center of the game- 



