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SUMMARY OF CURRENT RESEARCHES RELATING TO 
periphery. At the same time the nuclei swell up, and exhibit a thread- 
like structure ; they assume a very regular arrangement, and form a 
single layer in the parietal protoplasm. The chromatic threads next 
arrange themselves in the equatorial plane of the nucleus, and then 
divide into two groups of threads, each of which forms a daughter- 
nucleus. The daughter-nuclei again divide, and then two, or perhaps 
more, pass towards the centre of the oogone, and soon afterwards the 
cell-wall of the oospliere begins to form on the inner side of the parietal 
layer of protoplasm, leaving this, together with the remainder of the 
nuclei outside, to form the periplasm. From this mass of protoplasm 
and nuclei both the endospore and the exospore are formed. 
One or more antherids are developed in connection with the oogone. 
The antherids send out fertilizing-tubes, swollen at the ends, which 
pass to one side of the oosphere, come into close contact with it, and 
appear to open into it by a small aperture. The passage of a nucleus 
from the antberid into the oosphere has not been directly observed, but 
it is probable that fertilization does take place, as two nuclei have been 
seen in the oosphere at about the time when the nucleus or nuclei from 
the antherid appear to pass through the fertilizing-tube. 
The nuclei of the mycele divide in a similar manner to those of the 
oogone, but they do not become so large, nor exhibit the details so 
clearly. The gonids or zoosporanges contain numerous nuclei, differing 
in structure from those in the other parts of the plant. They consist of a 
central mass of protoplasm, surrounded by a layer of nucleoplasm, with 
a firm outline. They are spherical or slightly oval bodies, a little larger 
than the nuclei of the mycele. 
Smut of Wheat and Oats.* — Mr. J. C. Arthur states that Uztilago 
foefens B. & C. ( Tilletia Isevis Kuhn) may be recognized by its strong foetid 
odour, which is especially noticeable in the evening, or when the air is 
moist. If the spores of U. fcetens are placed under the Microscope, the 
black powder will be found to consist of an infinite number of round 
corpuscles, in the middle of which delicate ramifying filaments will be 
perceived, to which the spores are attached. The reproduction of this 
fungus is very simple. The spores forming the black powder are trans- 
formed, under certain conditions of temperature and humidity, into short 
branched tubes, and from these escape other minute spores. 
Endothlaspis-t — Prof. N. Sorokine, in his description of the materials 
for a Cryptogamic flora of Central Asia, gives the diagnosis of a new 
genus of Ustilagineae, Endotlilaspis. The filaments of the mycele destroy 
the ovary of the host. On the surface of the pistil the filaments divide 
by transverse septa and form the tissue. Each cell of this tissue is 
transparent and colourless, and is provided with a nucleus. In the 
interior of this pseudo-periderm the filaments of the mycele change into 
a mass of black or blackish spores. The author describes and figures 
two species:— E. Melicde , parasitic on the pistil of Melica ciliata ; and 
E. Sorghi , parasitic on Sorghum cernuum. 
* Bull. Agricult. Exper. Station, Indiana, Sept. 1889, 32 pp. See Rev. Mycol., 
xii. (1890) p. 90. 
f Rev. Mycol., xii. (1890) p. 4. 
