Speare : Massospora cicadina Peck 



77 



assuming the size and conformation of that part of the abdomen 

 which it formally occupied. In other specimens Plate 5, Fig. 1 

 B and D, the pustule is asymmetrical and ragged. Such speci- 

 mens as the latter are evidently old ones, from which a large part 

 of the conidia were detached when the hosts were alive and mov- 

 ing about. Upon microscopic examination the pustule is found 

 to be composed almost wholly of conidia, although if search is 

 made deep within the mass close to the septum, conidiophores and 

 the characteristic entomophthoroid hyphal fragments may also 

 be seen. 



As noted above, in the species of Entomophthora, the conidia 

 are violently discharged from the conidiophores. In Massospora, 

 however, the conidia are formed within the body of the host, and 

 although they are cut off in the usual manner their ejection is 

 prevented by the body wall of the insect, which when they are 

 cut off is intact, and holds them in the approximate position in 

 which they are produced. The conidia therefore cohere with one 

 another and a mass is formed which upon disintegration of the 

 intersegmental abdominal membranes is exposed, and assumes 

 the form of a pustule such as is described above. The movement 

 of the host at this period is perhaps the most important factor in 

 loosening the segments of the abdomen, the membranes connect- 

 ing which have been destroyed by the vegetative development of 

 the fungus so that the movements of the insects not only serve 

 to scatter the conidia of the fungus, but first free them from 

 captivity. 



The conidia are, so far as the writer has been able to determine, 

 all of one type, which conforms in most respects to that of the 

 other Entomophthorales. They are quite regularly oval in form, 

 measuring 10-14 X 14-17 microns. The papilla, an outgrowth 

 characteristic of the conidia of all members of the family, is usu- 

 ally not prominent, though always noticeable. Occasionally it 

 stands out conspicuously in a manner such as is shown on Plate 

 6, Fig. A. Unlike other members of the family, however, the 

 conidial walls are regularly verrucose, which condition renders 

 them unique in appearance. It should be noted, however, that 

 there is a tendency for them to lose the warted appearance if 

 they are permitted to remain in water for a short time. 



