130 THE SAPROLEGNIACEAE 



rey and Pieters, show the eggs not b}' any means filHng the oogonia. 

 Pieters does not mention or show the internal structure of the eggs in the 

 plant he studied. For other illustrations see Massee ('19), pi. 2, fig. 31. 



Fertilization occurs in this species, as Trow has shown in his 1904 

 paper, with about the same phenomena as he demonstrates in more 

 detail for A. deBaryana. Trow, however, does not claim positively for 

 this species a second division of nuclei in the oogonium before egg form- 

 ation. It is unfortunate that he gi\es no new data on the structure 

 of the mature eggs. It probably is almost like that of A. apiciilata. 

 DeBary describes the eggs oi A. gracilipes as "centric," but his figures do 

 not show the structure. 



Working at least in part on A. gracilipes, Scerbak (1910) tested 

 the efTect on diplanetism of various external conditions and found the 

 second swimming stage could be inhibited by osmotic pressure of the 

 medium and under the influence of narcotics, etc. The paper is in 

 Russian and only a short paragraph in German gives the conclusion. 



We quote the following discussion of synonymy by Humphrey 

 (p. 119): 



"It [A. polyandra Hildb.] is especially interesting as having been 

 the subject of a misunderstanding which has led to a confusion in syn- 

 onymy that I have here attempted to correct. It was undoubtedly 

 this species which Hildebrand described ('67) as A. polyandra. As 

 has been already pointed out, deBary gave the same name ('81) to a 

 distinct species which he recognized as differing from Hildebrand's de- 

 scription, but thought to be probably his species. At the time of the 

 completion of the paper quoted deBary had probably never seen this 

 form, as his later paper ('88) states that he first obtained it in January 

 of 1881, the year of the publication of the earlier one. And while he 

 did study it, he failed to notice its correspondence with Hildebrand's 

 figures and description, and therefore named it anew A. gracilipes. But 

 no one who will carefully compare the figures given by both authors 

 will, I think, seriously question that they represent the same species. 

 Again, Hildebrand states that secondary sporangia are not produced in 

 his A. polyandra, a statement that deBary ('81) disputes as untrue for 

 his A. polyandra. But in his description of A. gracilipes ('88), deBary 

 says that secondary sporangia are only sparingly developed, a statement 

 which I can corroborate for American specimens. The two descriptions 

 agree in all other essential points, so far as they are comparable; and 

 the evidence seems completely satisfactory that the correct synonymy 

 of this distinct species is as above given." 



