Entomogexous Fungi. 445 



Spokoteichum globdliferum on Yespa sp. (Probably 



Isaria sp.) 



On October 29, 1894, Mr. Pieteis found a specimen of Yes;pa sp. 

 almost covered with a thick felted growth of a white fungus. A 

 microscopic examination failed to reveal any characters which 

 would differentiate it from Sjyorotrichum globuliferum. The 

 heads of small spherical conidia were borne on threads exactly as in 

 tlie case of the typical specimens. A dilution culture was made 

 and the following habit of growth noted: germination becomes 

 apparent after about twenty four hours. One or two germ-tubes 

 are put forth which grow in a sinuous line and soon begin to 

 branch, throwing oft" a great number of cylindrical spores in the 

 agar. The protoplasm is hyaline. There are very few vacuoles 

 at first, but they soon appear, becoming plentiful at the end of 

 three days. In four days many of the cylindrical spores geim- 

 inate, putting out slender tubes and growing as in the case of 

 ordinary conidia. These cylindrical spores may be broadly oval 

 or long and slender. They are present in greatest numbers in the 

 places of crowded growth. The threads emerge from the agar on 

 about the fifth da;y. A loose, pufty, strongly elevated growth 

 appears, which soon becomes crowded with conidia. The threads 

 bear many short sterigmata at irregular intervals and irregularly 

 placed, often wliorled. These sterigmata bear from one to six oval, 

 nearly spherical conidia about If to 22 microns in size. The mul- 

 tiplication of these sterigmata and conidia soon forms in irregular 

 or spherical head. The threads anastomose freely. After ten days 

 the colonies attain the size of 2 am. in diameter, where they are not 

 crowded, the central two-thirds being colored white by conidia, the 

 outer margin being finely radiate in the agar. 



On potato, the growth spreads evenly and loosely over the sur- 

 face. A dense, firm weft is formed over the surface of the liquid. 

 At the end of six days the mycelium is creamy yellow where it 

 touches the glass. Later it turns buffs and sometimes almost red, 

 at the surface of the liquid. The white aerial mycelium sometimes 

 bears Isaria-sporophores, formed by the interlacing of threads, 2 cm. 

 or more in length. Cultures in Ehrlmeyer-flasks grow the same as 

 in tubes, except that the potato is colored slightly purple in the 

 near vicinity of the colonies, after about the seventh day. This 

 color usually fades out soon. Many strong sporophores are pro- 



