6 
Jour?ial of Mycology 
[Vol. 10 
paper ( 1 . c.) how it is quite possible that in Tertiary times the 
species could easily have passed from Europe to North America 
or vice versa. It is very likely that in even earlier times the 
condition of climate and topography of the two hemispheres 
might have been such as to have caused a wide distribution 
north and south before the modern types of the higher plants 
were evolved. The forms from Patagonia are shown in text 
Figures 27, 28, and those from Tibet in text Figures 29-32. 
The latter show peculiar variations in form. 
The species on which the genus was founded in 1890 by 
Lagerheim is H. hyalothecae, found on Hyalotheca dissiliens 
(consult the accompanying Plate). It was later found by Gobi 
in Finland, and by myself at Ithaca, N. Y., in 1903. At the 
same time (1903) the new species H. intermedium was found. 
Bibliographic references concerning the above species are given 
in the brief description of species at the close of this paper. 
The plants seem to show some relationship to such forms 
of the genus Rhizophidium as R. lagenula (A. Braun) Schroe- 
ter, 2 and the example of Chytridium lagenula A. Braun 3 which 
he figures on Conferva doccosa (bombycina ) looks very much 
like a young form of Harpochytrium hedenii Wille, but the de¬ 
scription and figure are too imperfect to be certain, while the 
mature forms of C. lagenula on Melosira varians are quite cer¬ 
tainly generically distinct, as is also R. fusus Zopf. 4 
Gobi 5 thinks the organism is an animal belonging to the 
Flagellates, and that algae like Characium, Ophiocytium, and 
Sciadium have been evolved from it. Wille, 6 while agreeing 
with Gobi that it shows a phylogenetic relationship with such 
algae, believes it is a chlorophylless alga derived from the green 
forms, much as he thinks the chlorophylless form Chionaster 
nivalis (Bohlin) Wille ( Cerasterias nivalis Bohlin) 7 has been 
derived by descent from the chlorophyll bearing genus Tetraedon. 
It does not seem necessary, however, to search in either of these 
directions for the relationship of the genus since a more probable 
and closer relationship exists with such species of Rhizophidium 
as I have mentioned above. A consideration of all the facts seems 
also to show that the organism is one of the Chytridiales, and the 
2 Rab. Krypt. Flora, 4 , p. 99. 
* A. Braun. Ueber Chytridium eine Gattung einzelliger Schmarotzer 
gewaechse auf Algen und Infusorien. Abhandl. d. k. Akad. f. Wiss. zu 
Berlin, pp. 21-83, Taf 1-4 (1885), 1856. 
4 Nova Acta physico-medico=Verhandl. d. Leopold. Car. Acad. d. 
Naturforscher, 47 , p. 199, Tab. 18, Fig. 9-12, 1884, Nuernberg, Erlangen, 
etc. 
5 Gobi, Chr. Fulminaria mucophila, Nov. gen. et sp. Script. Bot. 
Hort. Univ. Imp. Petrop. Fascic. 15 , pp. 283-292, Tab. VII, Fig. 1 & 2, 1899. 
8 Willie, N. Ueber Cerasterias nivalis Bohlin. Nyt Mag. f. Natur- 
videnskab. 4 /, pp. 171-176, 1903. 
7 Bolhin, K. Snoalgen fran Pite Lappmark, Botaniska Notiser, 
Lund. 1893. 
