336 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
names M. crustaceus. It actually penetrates the cells of the Mucor , 
living on their contents. 
M. P..Vuillemin * * * § identifies the parasite with the polymorphic species 
Trichoderma viride. 
Zygosperm of Sporodinia.f — M. M. Leger describes in detail the 
mode of formation of the zygosperm of a species of Mucorini, Sporodinia 
grandis. The two gametes, from the conjugation of which it is formed, 
are in every respect identical; there is no sexual differentiation. A 
special formation is described which has not previously been observed 
in similar cases. At the moment when the zygosperm appears to 
contain only a single nucleus, there is formed at each of its extremities, 
near the poles, a small spherical mass of a strongly staining substance. 
These bodies coalesce to form a kind of embryo, and the author 
believes them to have a very important function in the reproduction of 
the plant. He terms them embryonal spheres ; they are formed by the 
fusion of a large number of minute bodies, the embryogenous spheres , 
which appear to result from the dissolution of the old nuclei. 
Dispira4 — Under the name Dispira americana sp. n., Mr. R. Thaxter 
describes a new species of this rare genus of Mucorini, found on rat’s 
dung. The vegetative mycele is composed of rather irregular branching 
hyphse, for the most part non-septate, and much smaller in diameter 
than the fertile ones. From these vegetative hyphse are produced 
lateral branches, which, becoming slightly swollen terminally, attach 
themselves usually to the fertile hyphse of mucors. This lateral branch 
fixes itself firmly by a sucker-like tip, which eventually penetrates the 
host by means of an irregular protrusion. The suckers were the only 
parasitic organs observed. In the formation of the zygosperm this 
lateral branch, after it has fixed itself to the host, becomes divided into 
two parts by a septum, and these two parts conjugate with one another, 
the outer one becoming eventually separated from the parent-filament 
and receiving from the inner one the material derived from its parasitic 
union with the mucor. The outer gamete soon becomes nearly spherical, 
enlarging greatly to become the zygosperm, while the inner one sends 
out simple or once-branched finger-like processes, which grow about 
half-way round the mature zygosperm, and are at first yellowish ; 
they do not appear to have any very definite function. There seems to 
be eventually a direct connection between the contents of the mucor- 
liypha and the supplying gamete. 
The new species appears in some respects to have a closer relation- 
ship with Dimargaris than with Dispira. Both genera are placed pro- 
visionally among the Cephalidem. 
TJstilaginese.§ — Dr. O. Brefeld defines the characteristics of the 
Ustilagineae as the possession of basid-like fructifications, which ger- 
minate from the ustilagospores, and which may be regarded as the 
forerunners of the true basids of the Basidiomycetes ; while the ustila- 
* Tom. cit., pp. 258-60. 
f Kev. Gen. de Bot. (Bonnier), vii. (1895) pp. 481-96 (4 pis.). 
% Bot. Gazette, xx. (1895) pp. 513-8 (1 pi.). 
§ ‘Unters. a. cl. Gesammtgeb. d. Mykologie,’ Heft xii., Munster-, 1895, 236 pp. 
and 7 pis. See Bot. Centralbl., lxv. (1896) p. 326. Cf. this Journal, ante , p. 217. 
