304 CHARLES T. BRUES AND RUDOLPH W. GLASER. 



several papers of which that of 1910 in the Zoologischcr Ansc:gcr 

 is of greatest interest in the present connection. In Iccr\a pur- 

 chasl, he traced the entrance of the organisms into the egg of the 

 scale insect and its subsequent behavior through the formation of 

 the polar mass in the egg to the development of the mycetocyte 

 in the larva. He found that the individual symbionts of this 

 species were at first round or oval, and not noticeably elongated, 

 and that later during embryonic development and at the time of 

 hatching they became quite inconstant in form, varying from 

 rounded or oval to much elongated and frequently strongly 

 curved cells, all, however, of about the same diameter. These 

 long forms may fragment, each piece becoming a new individual, 

 while the short ones commonly divide by fission into equal parts. 

 Occasionally, however, Pierantoni found cells multiplying by 

 budding in the body cavity of the host, and more rarely in the 

 mycetome. 



On a gelatine medium, with high sugar content (20 per cent, 

 saccharose) he was able to cultivate a yeast-like organism from 

 the mycetocytes. These developed after four days' incubation as 

 colonies that are described as small spheres in the gelatine which 

 develop a sort of finger-like process which becomes prolonged 

 toward the surface of the gelatine and then emerges projecting 

 above it in the form of a finger, or with the base enlarged and 

 pyriform. The individual organisms were of yeast-like form with 

 buds more or less developed. It thus appears that the organism 

 obtained in culture by Pierantoni differed greatly in form, size, 

 and method of multiplication from the organisms in the insects, 

 as will be shown later, the cultures obtained by us from Puh'i- 

 naria innumerabilis exhibit no such remarkable distinctions, in 

 morphology and reproduction, from the cells in the host insect. 

 Although he makes no mention of the development of mycelia in 

 his cultures, the form of the colonies indicates without question 

 that such must have been present, and that if the organisms in 

 the mycetome were actually those obtained in culture, the 

 symbiont of Icer\a is a true fungus. 



