124 



COMPARATIVE MORPHOLOGY OF FUNGI 



tuberance which is abjointed. The empty hyphal cells break up so that 

 the mummy seems to be filled only by resting spores. In E. Culicis and E. 

 Delpiniana, the azygospores, like the conidia, arise as terminal swellings 

 of the hyphae (Fig. 76, 3 and 4) and then surround themselves with 

 double walls. 



In other species true zygospores are formed. In E. americana and 

 E. geometralis, two species with hyphal bodies arise in two different ways 



1 



8 



10 



Fig. 76. — Entomophthora Sciarae. 1. Young hypha. Entomophthora americana. 



2. Two gametangia fused at the tip, forming a lateral zygospore. Entomophthora Culicis. 



3, 4. Development of an azygospore. Entomophthora cchinospora. 5. Copulation. 

 Entomophthora sepulchralis. 6, 7. Development of a zygote. Entomophthora occidentalis. 

 8, 9. Copulation; the zygote develops from one gametangium at a distance from the point of 

 copulation. Entomophthora sphaerosperma. 10. Development of an azygospore. (1 X 

 180; 2 X 500; 3, 4 X 720; 5, 8 to 10 X 290; 6, 7 X 145; after Olive, 1906; Riddle, 1907, and 

 Thaxter, 1888.) 



(Riddle, 1907). In one case, hyphal bodies fuse near their tip and the 

 zygospore buds, as in Piptocephalis (Fig. 63), laterally from the point of 

 fusion (Fig. 76, 2). In the other case, copulation takes place, as in E. 

 Fresenii, through an H-formed piece, whereby the zygospores, as in 

 Syncephalis, are far removed from the point of fusion out of which a 

 gametangium grows. Caryogamy occurs only on germination. Similar 

 relationships are shown by E. occidentalis and E. echinospora (Thaxter, 

 1888), which do not break up into hyphal bodies but in which copulation 



