Entomogenous Fungi. 428 



color. The deep reddish perithccia are immersed in the light buff 

 stroma. Near the base the perithecia are more prominent. The 

 perithecia are conical, tipped with a pale yellow ostiolnm, which is 

 prominently pointed until the spores escape, when it collapses. The 

 distal half of the sporophore is fertile. The spores are thrown out 

 in a loose flocculent mass and remain clinging to the surface. They 

 are about 1^ microns in diameter, and have segments 3 microns in 

 length (Fig. 40). Eight spores are borne in a long tapering ascus 

 (Fig. 39), the base of which is usually broken in preparing mounts, 

 leaving the spores to protrude in a brush. The ascus is about 3^ or 

 4 microns in diameter. 



This specimen was carefully compared with four specimens from 

 Europe kindly loaned by Mr. J. B. Ellis. They differ slightly in 

 having perithecia somewhat less deeply immersed, but the measure- 

 ments are the same. The variety which is described on page 347 

 differs in having the perithecia not immersed, and in having the 

 spores much larger. It also develops into the typical form of 

 Isaria farinosa while the form under discussion produces a 

 conidial stage quite different. 



A dilution culture was made in the ordinary way using potato 

 agar. Many segments of spores were sown. They were taken 

 from the flocculent mass of spores protruding from the asei. No 

 other spores were visible except the typical ascospores, but when 

 germination took place, the growth appeared from rounded spores 

 much larger than those sown. This was doubtfully explained by 

 supposing that the large rounded spores were those of the corre- 

 sponding Isaria stage, which remained clinging to the sporophore 

 after the manner of Cordyceps clavulata. It also brought up the 

 case of the variety of Cordyctps militaris whose similar behavior 

 had been partially explained in the same way. This explanation, 

 however, did not make clear how the majority of the germinating 

 spores were rounded, while those sown were, so far as seen, small 

 and cylindrical. 



Accordingly another dilution culture was started, and this time an 

 examination was made soon after sowing. After one hour, numbers 

 of the true Cordyceps-spores were visible but no rounded ones. 

 After twenty hours there were visible many connected chains of 

 rounded bodies, closely resembling the conidia of laaria farinosa. 

 In several cases large portions of the ascus were visible, with nearly 

 all the segments of the spores swollen to the rounded form, and just 



