264 AQUATIC PHYCOMYCETES 



Resembling somewhat Phlyctochytrium biporosum Couch, but dif- 

 fering in the more pronounced beaks and in the nature of the rhi- 

 zoidal system. 



Rhizophydium haynaldii (Schaarschmidt) Fischer 



Rabenhorst. Kryptogamen-FL, 1 (4): 92. 1892 



Phlyctidium haynaldii Schaarschmidt, Magyar Novenytani Lapok. Kolozs- 

 var, 1883 (7): 58, pi. 2; Hedwigia, 22: 125. 1883. 



Sporangium sessile, oblong-ovoid or pyriform, with rounded base, 

 the apex bearing two broad diverging opposite tubular processes, 

 generally of equal magnitude, which when strongly opposed give a 

 triangular aspect to the sporangium; rhizoid delicate, unbranched; 

 zoospores from eight to ten, ellipsoidal, 2 \x long, with a long flagellum 

 and a colorless eccentric oil droplet, escaping individually through 

 pores formed at the tips of the two apical processes, movement hop- 

 ping; resting spore not observed. 



On Ulothrix zonata, Schaarschmidt (loc. cit.), Scherffel (in Moesz, 

 1938:72), (?) Spirogyra maxima, Berczi (1940:81, pi. 1, figs. 10-11; 

 pi. 2, fig. 11), Hungary; (?) Hormiseia imiflexa (coll. Andree), Lager- 

 heim (1899:436), King Charles Land, Arctic Region. 



In the shape of its sporangium and the possession of two apical dis- 

 charge pores the species resembles Rhizophydium rostellatum, Phlyc- 

 tochytrium biporosum, and Phlyctidium irregulare. Certain British spec- 

 imens doubtfully placed in Phlyctochytrium biporosum by Sparrow 

 (1936a: 443, fig. 3 m-n,p) may belong here. Serbinow (1907:157) 

 considers the species synonymous with Phlyctidium laterale, but the 

 configurations of the sporangia of the two species are totally unlike. 



The record of Lagerheim {loc. cit.) is of doubtful validity. It is 

 based on preserved material and is unsupported by figures or by an 

 adequate description. 



Rhizophydium chaetiferum Sparrow 



Occ. Papers Boston Soc. Nat. Hist., 8: 295. 1937; Papers Mich. Acad. Sci., 

 Arts, Letters, 24, Pt. I: 122, pi. 2, figs. 1-13. 1939 



Sporangium spherical, rarely subspherical, colorless, predominantly 



