ACHLYA 129 



This ]ilant witli its large eggs reminds one of .1. apiculata, hut I)y 

 careful obscr\ations and measurements it is found to differ from the 

 latter in the following ways: the eggs average about 44;x thick; the 

 oogonial stalks are short and straight; the oogonial walls arc thickened 

 and without an apiculus, and the oogonia arc closely packed with eggs. 

 In .4. apiculata the eggs average about 36ix; the oogonial stalks are long 

 and curved; the oogonial walls thin; and the oogonia only about half 

 filled with eggs. These characters while separating the present plant 

 from A. apiculata at the same time identify it as .4. megaspenna. 



Humphrey found the plant only once and then in cultures from 

 Spirogyra, dead leaves, etc., taken from a l)oggy spot by a small brook. 

 Our plant also has been collected but once, near Charlotte, N. C, by 

 J. X. Couch, February 12, 1921, and from a situation similar to that in 

 which Humphrey found it. -Mr. Couch has prepared the accompanying 

 plate. 



16. Achlya polyandra Hildebrand. Jahrb. f. wiss. Bot. 6: 258. pi. 16, 

 figs. 7-1 1. 1867. 

 ? Achlya gracilipes deBary. Bot. Zeit. 46: 635, pi. 10, figs. 2 and 6. 



1888. 



Pl.\te 5:^ 



This species has been reported in America only from Massachusetts 

 (Am herst) by Humphrey ('92, p. 119) and from Michigan by Pieters (in 

 KaufT man, '06). It is distinguished by the subcentric (?) eggs, the ab- 

 sence of pits in the oogonial walls, the rather long stalks of the oogonia, 

 and by the androgynous antheridia which spring as a rule from the 

 original stalks. We take the following description from Humphrey: 



"Hyphae stout, long. Zoosporangia often not abundant, secondary 

 ones rare, nearly cylindrical. Oogonial branches usually very long and 

 often recurved at the tip, racemose. Oogonia terminal, globular, with 

 smooth and unpitted walls. Antheridial branches arising chiefly from 

 the oogonial branches not far from the oogonia, often branched. An- 

 theridia one to several on each oogonium, short-clavate. Oospores 5 to 

 25, usually 10 to 15, in an oogonium, centric, their average diameter 2~'^." 



Humphrey thought that A. gracilipes deB. and A. polyandra Hildb. 

 were the same, but Pieters suggests that his figures of the European 

 plant (figs. 1-4) are exactly like those of A. gracilipes deB. and that 

 that may be a good species, different from A. polyandra. (It is, how- 

 ever, to be observed that in Pieters's figures the original stalks are not 

 recurved at the tips as in A. gracilipes.) Fischer regards Hildebrand's 

 plant as probably intermediate between A. gracilipes and A. polyandra 

 deB. It seems to us probable, however, that Humphrey is correct. 

 It will be noticed that both deBary and Hildebrand, as well as Humph- 



