998 AQUATIC PHYCOMYCETES 



In Closterium ehrenbergii, France. 



A resting structure was observed in only one instance and was 

 tentatively considered to be the resting spore of this species. 



The thallus resembles superficially Lagenidium entophytum, but in its 

 regularly cylindrical elements approaches L. rabenhorstii. In spite of 

 the lack of observations on the zoospores, the fungus is probably 

 correctly referred to Lagenidium. 



Lagenidium entophytum (Pringsheim) Zopf 



Nova Acta Acad. Leop.-Carol., 47: 154, pi. 13, figs. 10-18, pi. 14, figs. 1-5. 



1884 



(Fig. 81 A, p. 1002) 



Pythium entophytum Pringsheim, Jahrb. wiss. Bot., 1: 289, pi. 21, fig. I. 1858. 

 Myzocytium entophytum (Pringsheim) Cornu, Ann. Sci. Nat. Bot., V, 15: 21. 



1872. 

 Lagenidium americanum Atkinson, Bot. Gaz., 48: 336, fig. 6. 1909. 



Thallus consisting of an irregularly contorted bent relatively thick 

 tube bearing numerous short lateral variously oriented lobulations or 

 short branches; sporangia few, consisting of irregularly tubular lobulate 

 segments of varying length, delimited by thick refractive septate con- 

 strictions, the single discharge tube of each segment cylindrical or 

 somewhat irregular, 2 \x in diameter, of variable length, often swollen 

 at the point of contact with the inner wall of the host and locally 

 constricted where it passes through the wall; zoospores reniform, later- 

 ally biftagellate, 5-7 \x long by 4-6 \x wide, formed at the orifice of the 

 discharge tube, possibly surrounded by a vesicle; oospore lying singly 

 and loosely in a tabular segment of the thallus, spherical, 13-16.5 \x in 

 diameter, with a thick, golden, slightly dentate outer wall, parthenoge- 

 netically formed, germination not observed. 



Parasitic in the zygote of Spirogyra sp., Pringsheim (loc. cit.), zygote 

 and zygospores of Spirogyra sp., Zopf (loc. cit.), Minden (1915: 436), (?) 

 Euastrum luunerosum, Micrasterias mahabuleshwarensis var. wallichii, 

 Schulz (1923: 181, figs. 8-9), Germany; Spirogyra sp., de Wildeman 

 (1895b: 100, pi. 3, figs. 24-25), coll. Lemaire, de Wildeman ( 1896b: 47), 

 Spirogyra sp., Aleem (1952a: 2650, fig. 4), France; host (?), Scherffel 



