2 
Mas see, — A Revision of 
many years ago, before microscopic detail was considered 
to be an important factor in the discrimination of species, 
and up to now, these imperfect diagnoses have not been 
revised. The determination of a very fine species, recently 
received from Australia, suggested the necessity of a revision 
of the genus, and the following is an attempt in this direction, 
so far as practicable from an examination of the rich collection 
in the Kew herbarium. 
Morphology. 
A characteristic feature of the genus Cordyceps consists 
in the fact that the ascigerous condition always springs from 
a sclerotium, formed within the body of the insect on which 
the fungus is parasitic. In those instances where a conidial 
form is known, as in C. militarise the sclerotium is present 
before the ascigerous phase appears, but is not so compact 
in texture, and has not so completely destroyed the internal 
organs of the host at this period as when the ascigerous 
condition is developed. The conidial and ascigerous con- 
ditions are not met with at the same period, and it is probable 
that a considerable interval elapses between the appearance 
of the two phases ; a condition of things that would account 
for the ascigerous stage not immediately following the for- 
mation of conidia in artificial cultures. 
When fully developed, the sclerotium has completely 
destroyed and replaced the internal structure of the larva 
on which it is parasitic, the skin alone remaining intact ; 
structurally it consists of very compactly interwoven hyaline 
branched septate hyphae, replete with glycogen and minute 
oleaginous highly refractive globules ; when dry it is very 
compact and hard, and of a whitish colour. 
The ascigerous condition usually emerges from the sclero- 
tium at a point between two segments of the skin of the host, 
and most frequently in the cervical region ; it consists of an 
erect stem-like sterile portion, composed of a fascicle of 
irregularly parallel septate hyphae, white internally, the 
