176 — 



cells of the the sclerotia in from twelve to thirt}' hours, and im- 

 mediately produce basidia and conidia like the summer form, 

 (Fig. 6). As Miss Snow has remarked, "there is a striking re- 

 semblance between the 

 sclerotia bodies bearing 

 conidia and the later 

 stages of the ordinar}^ 

 conidia growths," as 

 seen in Fig. 3. Indeed, 

 during the autumn we 

 have seen all stages be- 

 tween the two ; and 

 although we have 

 termed the hyphal, co- 

 nidi a-beaiing filaments 

 of summer, the early or 

 summer stage, never- 

 theless this passes so 



Fig. 6. — Section of a sclerotium producing uew hj-phal ■ .^-i i , • ^ 4^\ ^ 



filaments and spores ; from a mid-winter experiment. imperceptlDl}' lUtO tnat 



.seen in Fig. 3, and the latter into the sderoiui7n, or winter coni- 

 dial stage, that the early stage and the sclerotia must be regarded 

 as extreme states of the same phase of life, resulting almost 

 wholly perhap.s, from climatic conditions. When any fungus 

 forms such sclerotium masses, the purpose is usually protection 

 against cold or dessication ; and this state takes the place of a 

 "resting spore," in the ca.se of a parasite, tiding the fungus over 

 to the next growing season of its host. As the sections of the 

 United States where these sclerotia have been noticed and reported 

 as abundant, namely, in Wi.scon.sin, by Professor Trelease, and in 

 Central New York, are in regions of rigorous winters, it would be 

 interesting to know whether they were as abundant in the south. 

 Certainly in this region the .sclerotia furni.shed one of the im- 

 portant and effective modes of carr>-ing the fungus over the 

 winter. 



The perithecia, constituting the fourth state mentioned, begin their 

 development in late autumn, but are not mature in our latitude until 

 March or April. They are found about, or occasionally upon tlie 

 white center of a spot on an old, apparenth- dead leaf. The)' can 

 be seen with the naked cj'e, as minute black points. Externally 

 the wall is nearl)'' black, and composed of large cells. The cavity 

 of the perithecium is lined with dehcate, white cells. At the apex 



