400 QUARTERLY CHRONICLE OF MICROSCOPICAL SCIENCE. 
rotating mass.'!| In Hydrodictyon he also figured a double 
spore. In all these genera in which these monstrous unions 
have been observed normal conjugation is now believed to 
take place. It is very difficult to suppose that the two things 
have nothing to do with one another. 
Hydrogastree.—Rostafinski has made a most interesting 
discovery respecting Hydrogastrum. This curious little alga 
has hitherto been placed amongst the Siphophycee.’ It turns 
out, however, not to belong to the Oosporee, but to the 
Zygosporee. The resting spores which have been described 
by Cienkowski under the name of Protococcus botryovdes, 
when placed in water, give origin to zoospores which imme- 
diately conjugate. This takes place, Rostafinski assures me, 
with sufficient precision to enable it to be employed as a 
class demonstration. Inasmuch as Sorokin has observed 
conjugation in the Chytridineous genus Tetrachytrium,’ it 
may be suggested that the real affinity of Hydrogastrum is 
with the Chytridiee. There will then be a relation between 
Hydrogastree and Chytridiee amongst Zygosporee, similar 
to that between Stphophycee and Siphomycetes among 
Oosporee. 
Rostafinski proposes that Sach’s ZyGosporEm should be 
divided into Jsosporee and Conjugate, the former group to 
contain ali forms in which the conjugation of zoospores 
occurs. What Areschoug terms a zygozoospore he proposes 
to call an isospore. There can be no doubt that this is a 
pleasanter terminology to use. 
Volvocinee.—The observations of Carter upon Eudorina 
have been confirmed by Gorojankin.* 
Stphophycee.—In Bryopsis Janczewski and Rostafinski 
consider® that the bodies which Pringsheim supposed to be 
the antherozoids (supra, pp. 313, 314) are really parasitic 
Chytridineous organisms. It is an open question so far 
whether Bryopsis may not, like Hydrogastrum, turn out to 
belong to the Zygosporez. The zoospores also exhibit the 
propensity to “agglomerate,” and, judging from other in- 
ae this suggests the probability that they conjugate 
also. 
Pheosporee.—Janczewski and Rostafinski® studied zoo- 
spores of various species at Cherbourg during 1872, with 
'T have copied one instance from him (supra, p. 305). Perhaps I should 
have put a ? after ‘ Conjugation.” 
2. Parfitt has given a strangely erroneous account of its life-history in 
* Grevillea,’ vol. i, pp. 103-105. 
3 Supra, p. 307. * Supra, p. 310; Rostafinski, |. ¢., p. 145. 
® Loe. cit., p. 375. 6 Loe. cit., p. 371. 
