Speare: Massospora cicadina Peck 



73 



mentioned brief note of Thaxter no other publication has ap- 

 peared, as far as the writer is aware, in which the microscopic 

 characters of the fungus have been considered. 



Like the host which it parasitizes, Massospora cicadina is, so 

 far as is known, peculiar to America, and as a result, Europeans, 

 to whom the fungus is known only by such fragmentary and in- 

 complete references as those noted above, have been more or less 

 confused in regard to the nature of the organism, Lakon (1919a), 

 for example, classing it with Sorosporella agrotidis Sor. (Soro- 

 sporella nvclla (Krass.) Gd.) and Massospora staritzii Bresa- 

 dola as " Unvollkommen bekannte Entomophthoreen bezw. als 

 solche beschriebene Pike." 



During the summer of 1919, Brood X of the periodical cicada 

 made its appearance in the vicinity of Washington, D. C, and an 

 excellent opportunity was thus afforded the writer to study its 

 fungous parasite. The later was first observed on May 31, about 

 ten days after the first insects emerged from the earth, and from 

 this date until the disappearance of the brood in the early part 

 of July it was constantly present, though in no great abundance 

 until after June 10. 



The resting spore as well as the conidial condition of the fungus 

 was common about Washington, in 1919, but the latter was never 

 as abundant as the former, and while it was often a difficult 

 matter to collect during an afternoon a dozen cicadas showing 

 conidia, during as many hours later in the season it was not dif- 

 ficult to collect hundreds of specimens showing the resting spores. 

 It should be noted, that both types of reproductive bodies 

 were never found either simultaneously or consecutively in the 

 same individual, and it was determined that the conidia and the 

 resting spores occurred at different periods in the aerial life of 

 the host, the former appearing exclusively in the early part of the 

 season, the latter developing toward the end of the aerial exist- 

 ence of the insect. It should be noted furthermore that the fun- 

 gus seemed to be largely though not exclusively confined to the 

 male insects. Despite the fact that infected insects were observed 

 and collected many times during the season, not more than half 

 a dozen parasitized females were observed. Whether or not the 



