256 BOTANICAL GAZETTE [APRIL 
lium is produced, which in early stages is few septate; later, how- 
ever, at the culmination of vegetative activity, septa are abundant and 
branching becomes more frequent. 
Finally, the body-cavity becomes almost completely filled wii the 
mycelial filaments, vegetative activity ceases and the death of ‘the 
insect ensues with the beginning of the fructifying condition. 
Radial branches, which mark the beginnings of the conidiophores, 
are put forth from the short, 3-5-nucleate cells which make up the 
mature mycelium; in this species, but one branch grows from each 
cell. These radial hyphae bore their way out through the body-wall of 
the insect; some form the rhizoids which attach the host to the sub- 
stratum, while others grow into branched conidiophores. Each conidi- 
ophere is cut up by cell-division into uninuclueate segments, each of 
which pushes out beyond the surface of the host and cuts off from its 
tip a single uninucleate conidium. The basal cell below the conidium 
comes to possess but a thin, enucleate primordial utricle, and it finally 
becomes greatly swollen from the absorption of water. Ultimately 
this swollen basal vesicle bursts in a ring at the top where it joins 
the conidial wall, or the columella-like wall may be split in some 
instances, and the conidium is thus shot violently away, the slimy 
protoplasmic contents of the lower cell being frequently carried along 
with the conidium and serving to stick the latter to the substratum. 
The partition which cuts off the conidium is at first curved upward by 
the greater turgescence of the vesicle; but when the spore is shot off, 
this reverses its former position, and in the conidium it appears as 
a prominent papilla. 
a. uclear division—The nuclei of Empusa are “centronu- 
clei,” since the centrosomes which are active during division are 
permanently intranuclear. 
The division of the nuclei which takes place during the vegetative 
stages appears to be of the nature of a primitive mitosis, similar in 
many respects to that described for certain of the simpler Protozoa. . 
The nuclear membrane generally persists during the whole process. 
A simple intranuclear figure is formed, which in later stages consists 
of the two opposed centers of division, to each of which converges from 
all sides a system of fibrous radiations. The many radiations which 
converge at the two poles correspond to the chromosomes; and, 
