1897 ] LHE PHALLOIDE AL OF THE ONITED STATES ri 
In 3 hrs. 35 min. the half in water made an amount of elon- 
gation 20™ greater than that made by the half in moist air dur- 
ing 25 hrs. 15 min. The experiment seems to indicate that the 
rapidity of elongation is favored by an abundant supply of 
water, but that any very appreciable amount in addition to that 
already contained in the egg is not, perhaps, absolutely neces- 
sary. This experiment was made with the last egg available. 
The same conclusion, however, had been rendered probable by 
earlier experiments in which more resistance to its elongation 
was met with by the half of the egg in the moist atmosphere. 
A very large part of the substance of the egg is comprised 
in the volva itself, the greater portion of which is a thick middle 
layer, very gelatinous, and containing a large amount of mois- 
ture. As already shown, the differentiation of the volva is one 
of the earliest processes in the development of the egg.5 At 
the time of beginning of differentiation of the basidia in Mutinus 
caninus, the middle layer of the volva has already undergone 
gelatinous modification, and has attained a thickness of about 
one-third of the diameter of the egg, and has come to inclose 
the tissue of the future receptaculum and gleba at the top and 
sides — everywhere except at the very base of the egg where 
the vegetative mycelium of the fungus is in communication with 
the more central structures.6 This relation of the volva to the 
inner parts is retained through all the later development of the 
egg until the spores are mature and elongation of the receptac- 
ulum occurs. What is the function of the volva? Is it pro- 
tection? Perhaps such varying external conditions as a hot, 
dry atmosphere or a flooded condition of the soil during heavy 
Storms are prevented by the thick, gelatinous layer full of 
moisture from exerting a too direct and injurious effect on the 
inclosed developing gleba and receptaculum. Instaining young 
eggs for sectioning in my studies of several species of Phal- 
loidez, I find that aqueous stains do not penetrate through the 
volva so as to give a good stain to the gleba and receptaculum 
5Bor. Gaz. 22: 276. Jig. 4. 1896. 
© Ann. of Bot. 10: 352. fig. 5. 1896. 
