AN ACHLYA LACKING SEXUAL REPRODUCTION 
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were formed in addition to the sex organs or took their place. Walz, 
however, does not mention the zoosporangia or the sex organs; but 
from his naming the form so definitely, we must infer that he observed 
the sex organs of the species. 
In quite a different category from the occasionally induced struc- 
tures just considered, must be placed the resistant bodies which are 
regularly produced in the life cycle of certain Saprolegniaceae forming 
sex organs only rarely, or even lacking them entirely. 
In the genus Saprolegnia there have been reported a number of 
forms of this kind. Lindstedt (10) described a species of Saprolegnia 
which produced zoosporangia and zoospores typical of the genus, 
followed by spherical, pyriform, or more irregular bodies capable of 
germinating at once by characteristic Saprolegnia zoospores, or of 
remaining temporarily inactive and later germinating by a tube or by 
zoospores on the renewal of favorable conditions. Maurizio (11) 
also recorded three undetermined species of Saprolegnia which, after 
the formation of the characteristic sporangia, produced not sex organs 
but the irregular ''Sporangienanlagen " which he considered significant 
from the phylogenetic point of view. In all probability conditions of 
culture are responsible for the behavior of the fungi in these instances; 
since the method employed by both Lindstedt and Maurizio are shown 
b}^ the exact physiological investigations of Klebs (7) to favor "gem- 
mae" formation, and to hinder the development of sex organs. In 
like manner the failure of Lechmere's (8) more recently described 
species of Saprolegnia to form oogonia under continued cultivation 
may be ascribed to his culture methods. Although Lechmere used 
pure cultures, he employed as a nutrient substratum egg albumin, a 
substance readily broken down into injurious compounds by the 
activity of the fungus. Indeed he even mentions (p. 168) changing 
the water of his cultures every day to keep them fresh. Had his cul- 
ture conditions been more favorable, it is reasonable to expect in the 
light of Klebs's investigations that the sporangia would not have 
presented such confusing abnormalities of development; and the 
torulose ''gemmae" would readily have given place to the normal 
oogonia of the species {Saprolegnia toriilosa) which Lechmere later 
(9) determined this fungus to be. Recently, however, Pieters (15) 
has subjected certain species of Saprolegnia to exact physiological 
investigation with interesting results. One of these forms, Saprolegnia 
Kauffmaniana, characteristically produced numerous sporangia and 
