WITH NOTES ON OTHEE SPECIES. 127 



that an oogonium may contain as many as eight or ten oospores ; but I have never 

 seen more than four, and his figures show no more than three. He describes no special 

 antheridial branches, but says that the antheridia are like those of A. dioica Pringsh, 

 As these latter are not antheridia at all, one would expect to find, as is the case with 

 American specimens, that the species has no true male organs. As will be seen from 

 the figures, the spines could hardly be more closely set, and their form is more cylin- 

 drical than conical. 



This and the next species seem to be closely related, the more so if the Ameri- 

 can form here described proves to be more typical than Archer's. 



Achlya stellata DeBary ('88). 



111.: DeBary, '88, Pl.X, Figs. 10, 11. 



Like the last, to which, indeed, it seems almost too similar, this plant has no 

 antheridia. Its globular or elliptical oogonia are covered by rather less numerous 

 spines that are shorter and sharper, therefore more conical, than those of ^. cornuta. 

 The oospores are always single and sometimes correspond in form with the cavity of 

 the oogonium, instead of being always globular. It is known only from a single 

 locality near Gottingen. 



Species inquireistd^. 



Achlya contorta Cornu ('72, PL I, Figs. 9-15), with smooth oogonia, containing on 

 an average eight oospores, and borne on long, spirally twisted branches with peculiar 

 local swellings, and with branched cylindrical antheridia ; and Achlya leucosperma 

 Cornu ('72), with antheridia similar to the last, and oogonia with two-pitted walls 

 and light-colored oospores, have been studied only by their author, whose descrip- 

 tions are too imperfect to determine their position. While they may prove to be 

 distinct species, more definite and complete information concerning them is much 

 needed. 



Achlya dioica Pringsh. ('60, PI. XXIII, Figs. 1-5), should be written as a 

 synonym, probably of some species already described ; but as the oogonia were not 

 mentioned or figured, it is impossible to say to what species it belongs. The name 

 was given to some hyphse said by the author to be those of an Achlya, which were 

 attacked by a Chytridiaceous parasite, probably that since described by Cornu ('72) 



A. p. S. — VOL. XVII. Q. 



