May 10,1924 Botryosphaeria and PTiysalospora on Currant and Apple 591 
RELATIONSHIP OF 
THE FUNGI HAVING 
DOTHIORELLA TYPE 
PYCNIDIA OF THE 
a3 O 
oil 
PERCENT OF TOTAL 
FOUND IN EACH 
Oi o o« 
SPORES 
CLASS 
O 
o, 
t\> 
ro 
to ^ 
M S{ 
The collection and growth 
in pure culture of so large a 
quantity of material for 
study of the life histories 
the fungi, and especially the I 
fact that a very large propor- g 
tion of the cultures fruited in| 
less than two months from the § 
time they were made, has en- o 
abled us to make a more careful § 
comparison of the fungi con-'g 
cerned than has hitherto been 
possible. Although the study § 
has included material from a * 
variety of hosts and from s 
widely separated localities it is g 
proposed to discuss here only ^ 
the forms which are known to « 
occur on apple and those de- §- 
scribed by Grossenbacher and^g 
Duggar on currant. ® 
The writers’ studies of the g, 
O 
currant cane blight fungus and e 
its saprophytic form have ex- | 
tended over a period of six g 
years and have included the*g 
more important currant-pro- S', 
ducing regions of the United a 
States. In general, the caref ul | 
work of Grossenbacher and | 
Duggar has been fully con- § 
firmed. The parasitism of the g. 
form which is characterized by ™ 
the production of a bright pink g* 
color on starchy media has§. 
been confirmed by inoculation ^ 
experiments in Virginia, both ^ 
outdoors and in the green- 3 
house, as well as in Connecti- g 
cut and Massachusetts. Inoc- § 
ulations with the non-chro- Z 
mogenic form have given uni- g- 
formly negative results. g 
Continued collecting has, as •§ 
might be expected, resulted in S> 
finding that the ascospores 5 * 
vary through a somewhat § 
wider range than that given by g- 
Grossenbacher and Duggar,» 
the great majority of the & 
spores, however, fall within |* 
the limits set by them namely, w 
ascospores, 16-23 ju by 5-7 ju, 
and pycnospores 16-31 by 
4.5-8 n. Moreover, it is apparent that the size of the stromata varies very 
widely and is dependent to some extent on the thickness of the bark within which 
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