BLA STOCLA DIA LES 67 1 



Resting spores with broadly rounded apex, cytoplasm colorless. . . . 



A. neo-moniliformis, p. 677 



Life cycle of the Brachyallomyces type A. anomalus, p. 678 



Group Euallomyces 



With alternation of isomorphic asexual and sexual generations; rest- 

 ing spore persistent on plants, pits on wall closely spaced, germinating 

 to form planonts which give rise to sexual plants. 



Allomyces arbuscula E. J. Butler 



Ann. Bot. London, 25:1027, figs. 1-18. 1911. Emend. Hatch, J. Elisha 

 Mitchell Sci. Soc, 49(1): 163. 1933 

 (Fig. 40 A, p. 616; Fig. 41 Q-V, p. 622; Fig. 42, p. 626) 



(?) Blastocladia strangulata Barrett, Bot. Gaz., 54:367, pi. 18-20. 1912. 

 (?) Allomyces strangulata (Barrett) Minden, in Falck, Mykolog. Untersuch. 



Berichte, 2(2): 214. 1916. 

 (?) Septocladia dichotoma Coker and Grant, J. Elisha Mitchell Sci. Soc, 



37: 180, pi. 32. 1922. 

 (?) Allomyces arbuscula forma dichotoma (Coker and Grant) Kanouse. 



Amer. J. Bot., 14: 303. 1927. 

 Allomyces kniepii Sorgel, Nachrichten Gesell. Wiss. Gottingen, Math.- 



Physik. Kl., Fachgruppe VI (Biol.) (N. F.), 2(10): 155. 1936; Zeitschr. 



Bot., 31:402, figs. 2-10. 1937. 

 Allomyces arbuscula var. arbuscula Emerson, Lloydia, 4: 136. 1941. 

 Allomyces arbuscula var. minor Emerson, Lloydia, 4: 136. 1941. 



Basal cell conspicuous, 100 200 \x long by 60-100 u. in diameter, 

 hyphae copiously sympodially or dichotomously branched, the pseudo- 

 cells up to 250 \x long by 15-25 \x in diameter; sporangia single or caten- 

 ulate, broadly ellipsoidal or ovoid, with rounded or truncate ends, 40 - 

 70 [jl long by 30-40 \x in diameter, forming from one to four discharge 

 papillae; zoospores ovoid, oblong, or ellipsoidal, 12 [x long by 6 a in 

 diameter; resting spores abundant, ovoid, with rounded apex and trun- 

 cate base, 28-67 \x long by 16-45 \x in diameter, 1 exospore thick-walled, 

 tawny to reddish brown, minutely punctate, upon germination forming 

 posteriorly uniflagellate planonts; sexual thallus similar to the asexual, 

 gametangia at first terminal in pairs, later catenulate, alternating, the 



1 From Emerson's data (1941) on this strain, "North Carolina No. 2." 



