igoS] EDGERTON—ANTHRACNOSES 387 



The pcrithecia from the Illinois collection were single or collected in 

 twos or threes partially or nearly imbedded in the tissue of the host, 

 and the necks wTre surrounded by a thin layer of pseudo-paren- 

 chymatous fungus tissue. They were generally about 70-125X175- 

 225 /x, the necks being sometimes 50-60 />t in length. The perithecial 

 "wall was composed of three or four layers of narrow, long, black, 

 thick-walled cells. Sometimes two pcrithecia fused, so that there was 

 one internal cavity with tw^o ostioles. At the base of the pcrithecia 

 there were generally large, dark-colored hyphae made up of nearly 

 globose cells 6-% fx in diameter (these show plainly in the photomicro- 

 graph) . Fig. 75 was made from apples received from Missc uri. The 

 pcrithecia here were not imbedded in the host tissue, but were at 

 the base of the conidial stroma; and the perithecial wall gradually 

 blends into the pseudo-parenchymatous fungus tissue- Necks were 

 almost entirely lacking on these perithecia; in other points they 

 were identical with those described above. 



The pcrithecia develop readily on bean agar, the best success 

 having been obtained with that medium. They appear in raised 

 masses or nodules scattered over the siu-face of the plates. These 

 masses are black, and by the time the asci arc mature they may be 

 2 to 3^"^ in diameter. The pcrithecia {fig. 13) form around a small 

 stroma of pseudo-parenchymatous tissue, and are quite variable in 

 shape and size, being 80-140 /^ thickX 1 20-225 /^ ^^^o* Thp apex may 



ery 



seems 



them 



opened directly into the underlying agar. In a plate 

 kept in the incubator at a temperature of 26-30° C, the nodules of 

 perithecia were generally visible in four to six days, and the asci 

 were generally mature in sixteen to twenty-one days. 



The asci are 50-80X8-10 /*, clavate, almost entirely fiUed by the 

 eight spores; the wall is hyaline and sometimes difficult to see except 

 with fresh material. The spores are hyaline, slightly curv-ed, rounded 

 at the ends, granular, and possess a large clear nucleus near the center 

 and on the concave side of the spore. The spores are irregularly 



cry 



The 



asci go to pieces and the spores ooze out of the neck of the perithecia. 



What 



