SAPROLEGNIALES 843 



plished by a slender germ tube ultimately terminating in a zoosporan- 

 gium" (Johnson, 1956). 



Type species: Achlya prolifera C. G. Nees. 



The recognized 1 species are those treated by Johnson (1956). 



APHANOMYCES de Bary 



Jahrb. Wiss. Bot., 2: 178. 1860 

 (Fig. 65 Q-R, p. 836) 



"Hyphae very delicate, long, sparingly branched. Sporangia formed 

 from unchanged hyphae, long to very long, not proliferating within 

 old ones and rarely laterally from below. Spores borne in a single row, 

 emerging apically in elongate form, then rounding up and encysting in 

 a clump at end of the sporangium as in Achlya, then emerging and 

 swimming again as in that genus. Specialized gemmae lacking. Oogonia 

 terminal on short or long branches, smooth, warted, or spiny; wall 

 thin or thick and irregular; eggs single, not filling the oogonium (nearly 

 so in some species), of various structure. Antheridia diclinous or 

 androgynous, not always present" (Coker and Matthews, 1937). 



Type species : Aphanomyces stellatus de Bary. 



TAXA NOT IN COKER (1923) OR COKER AND MATTHEWS (1937) 2 



Aphanomyces acinetophagus Bartsch and Wolf 

 Amer. J. Bot., 25: 394, figs. 1-9. 1938 



Explanation of Figure 66 



A-B. Protoachlya paradoxa Coker: A, sporangia; B, sex organs. C. 

 Plectospira myriandra Drechsler, discharged lobulate sporangium. D. Aphan- 

 odictyon papillatum Huneycutt, sporangia, one of which is discharging zoo- 

 spores. E. Aplanes androgynus (Archer) Humphrey, sporangium and sex 

 organs. F. Aphanodictyon papillatum Huneycutt, sex organs. G. Sommerstorf- 

 fia spinosa Arnaudow, thallus epiphytic on an alga, bearing three capturing 

 organs and a parasitized rotifer from which a zoosporangium emerges. 



{A-B, Coker, 1923; C, Drechsler, 1927; D, F, Sparrow, 1 950 ;£, de Bary, 

 1888; G, Sparrow, 1929) 



1 Vishniac and Nigrelli (1957) do not accept Johnson's reduction to synonymy 

 with A. racemosa of A. sparrowii Reischer (1949b). 



2 See also Benisch(1940), and Ziegler in Mycologia, 50 : 403, 1958 {A. mucronata). 



