starvation of vegetable and animal tissues. 53 
In regard to both animals and vegetables the procedure em- 
ployed in carrying out the experiments was similar, consisting 
in retaining them for various periods in fluids in which nutritive 
material was present in various amounts, or almost entirely 
absent, the latter condition being secured by employing distilled 
water as a medium. With these preliminary observations a 
detailed account of the results of experiment may be entered 
upon. 
I. — Experiments on the Effects of Deficient Sn,pply of Nutritive 
Material on Vegetahle Tissues. 
The plants subjected to experiment were, as before mentioned, 
both members of the mucorine order of fungi ; one of them 
being the sole known representative of the genus Choanephora, 
the other the well-known Pilobolus crystallinus. Both of these 
fungi are of constant occurrence in the neighbourhood of Cal- 
cutta, and both are readily susceptible of cultivation in media so 
liquid as to allow of the easy removal of germinating conidia 
and spores, or portions of mycelium and fructification, with a 
minimum of disturbance or injury. This is naturally a matter 
of moment when it becomes necessary to submit such structures 
to minute examination, or to transfer them to new media. In 
so far as Choanephora, however, is concerned, the nutritive fluid 
itself, a strong decoction of the corollse of Hibiscus, is such as 
to allow of continuous observation of all the stages of growth 
in the fungal structures while still in it, and of ready dilution 
with, or entire substitution by, distilled water without any dis- 
turbance of the mycelium. 
The conidia of Choanephora when introduced into the nutri- 
tive fluid germinate almost immediately, and under ordinary 
circumstances produce an abundant crop of conidial fructification 
within twenty-four hours. Immature conidia are full of a 
coarsely granular oily protoplasm, but they clear up greatly as 
they ripen, and ultimately the oily matter is only represented by 
aggregations of yellowish granules, one of which is generally 
situated toward either extremity of each oval conidium. When 
the conidia are subjected to conditions permitting of their ger- 
mination, the first change which occurs in them is a gradual 
diffusion of the fat granules, and the establishment of streaming 
movement in the protoplasm. Ultimately the granules dissolve 
and almost entirely disappear, and the conidium, now full of 
shining, active protoplasm, emits a germinal tube. The latter 
grows and ramifies rapidly if the surrounding fluid contains 
sufficient nutritive material, and within the course of a few hours 
gives rise to an abundant mycelium. Where the fluid is deficient 
