1910] CURRENT LITERATURE 311 
narum I”’ records ro species and several varieties as new to science.—F. A. WoLF 
(Mycologia 2:19-22. pl. 18. 1901) has published a new species of Fusarium, 
parasitic on Viola tricolor —H. Wo.Fr (Rep. Nov. Sp. '7:345, 346. 1909) has 
published a new species of Eryngium (E. affine) from Costa Rica —C. H. WricHt 
(Kew Bull. 24. 1910) describes a new species of Urceocharis from Peru.—Different 
authors (ibid. 357-362. 1909) under the heading ‘‘Decades kewensis LIV” have 
published a number of new species of flowering plants, including a new genus 
(Micholtzia) of the Asclepiadaceae from India; also a new genus (Ennealophus) 
of the Iridaceae from Brazil.—J. M. GREENMAN, 
A new genus of chytrids.—A minute organism parasitic in the leaf blades 
and petioles of the ragweed (Ambrosia artemisiaefolia) is described by Griccs3 
as a new genus. The swarm spores perforate the cell wall and enter the cells 
(epidermal, hypodermal, or chlorenchymal), sometimes in large numbers, where 
they present amoeboid forms within the plasma of the host. Some of the ‘‘amoe- 
bulae” unite in pairs by the fusion of their plasma while the nuclei remain distinct. 
This minute amoeboid zygote grows to form a binucleate resting spore which at 
maturity is provided with a stout exospore wall. The germination has not been 
studied. Other swarm spores, in the same or other cells, grow to form zoosporan- 
gia about 70 # in diameter, showing also amoeboid movements in the vegetative 
Stage. The nucleus of the young “amoebula” which is to form a zoosporangium 
is said to “fragment” into four nuclei at an early stage. Since the figure given 
presents just as much evidence that the four nuclei are derived by mitotic division 
as by fragmentation, it would be interesting to know if this is the period of meiosis. 
A rather extended period then follows before further successive division of these 
four nuclei to form the zoospores, which are 2.5 . The author saw no mitotic 
figures, but states that'in some cases at least there is evidence that the nuclei 
fragment. The formation and escape of the zoospores was not observed, and he 
does not know whether the zoospores are ciliate or amoeboid, the latter he thinks 
more likely. Since the escape of the zoospores was not observed, he does not know 
Whether or not an exit tube is formed from the sporangium. The species, which 
he names M. stevensianum, is associated with Rhodochytrium spilanthides, and 
while the infected cells increase greatly in size, very little deformity of the host 
occurs, although large numbers of cells in a limited area are affected. 
Some of the speculations appear to be based on a misinterpretation of some 
Statements of the reviewer in regard to the behavior of the zoospores of Rhizophid- 
tum, for he says: “ATKINSON has shown that when liberated inside the sporan- 
gium the zoospores swim actively forward until they strike the wall of the sporan- 
gium, when the flagella are retracted and the zoospore puts out pseudopodia by 
which it gropes for the opening of the sporangium. In case it is located too far 
from the ostiole to reach it with its pseudopodia, it resumes its flagellate form and 
hts 
3 Grices, R. F., Monochytrium, a new genus of the Chytridiales, its life his- 
tory and cytology. Ohio Nat. 10:44-54. pls. 3, 4. 1910. 
