6 Mas see. — A Revision of 
as Isaria fuciformis , Berk., occur as true parasites under 
certain conditions, although usually developing as sapro- 
phytes, thus leading up to such truly facultative parasites 
as Isaria farinosa, the conidial state of Cordyceps militarise 
and Isaria densa , which Giard has some reason for suspecting 
to be the conidial condition of Cordyceps entomorrhiza . 
The genus Hypocrea — as understood in the broader sense — 
may be looked upon as the type of a number of genera, 
characterized as such more by the amount of faculative 
parasitism acquired by their respective conidial forms, than 
by any strictly morphological characters. The majority of 
species included in the genus Hypocrea are undoubtedly true 
saprophytes throughout the cycle of their development ; at 
the same time, some exotic species, whose life-history is 
unknown, occur on a vegetable matrix which from appearances 
suggests parasitism, and in the case of certain species occurring 
on coriaceous leaves, there appears to be very little room 
for doubt on this point. Epichloe , an allied genus, is mainly 
characterized by having both the conidial and ascigerous 
condition developed in the form of a sessile, effused stroma 
on the culms of living graminaceous plants. In the genus 
Claviceps , parasitic on the fruits of graminaceous plants, we 
have a higher stage of development ; a conidial condition 
first appears, followed by the formation of a compact, 
external sclerotium, which after a period of rest, produces 
the highly differentiated, stipitate ascigerous form of fruit. 
It remains to be explained why the members of the two 
genera last mentioned confine their attacks to plants belong- 
ing to the order Gramineae. Cordyceps differs mainly from 
the last-named genus in being parasitic on insects, and in 
the sclerotium being formed within the body of the host ; 
the additional character of the spores breaking up into their 
component cells, as given by Saccardo 1 , being of no value, 
inasmuch as the spores of some species of Cordyceps are 
continuous, as in Claviceps . The ascigerous condition of the 
1 Sylloge Fungorum, Vol. ii, p. 566. 
