562 AQUATIC PHYCOMYCETES 



across the lumen; operculum surmounting the discharge papilla, shal- 

 lowly convex, 10-30 \x in diameter; zoospores hyaline, spherical, 6-6.5 y. 

 in diameter, with a basal hyaline globule 2-2.3 \x in diameter, and a 

 flagellum 32-35 [i long, emerging in a mass imbedded in a matrix with 

 the flagellum coiled around the body, the flagellum soon uncoiling and 

 assuming motility; resting spore spherical (8-20 [i), oval (9-14 by 12- 

 17 jx), narrowly elongate, or angular, with coarse granular contents, the 

 dark-brown wall usually smooth, occasionally rugose or verrucose, 

 germination not observed. 



Saprophytic on chitinous substrata, United States. 



Distinguished by its large operculum and smooth to rugose or 

 verrucose resting spores. In having nearly catenulate rhizoids the 

 species resembles one of Catenochythdium. The dehiscing of the oper- 

 culum sometime prior to zoospore discharge and its elevation on the 

 inner hyaline papilla is occasionally seen in other chytrids. 



Karlingiomyces marilandicus (Karling), comb. nov. 

 Karlingia marylandia Karling, Mycologia, 41:518, figs. 70-78. 1949. 



Sporangium with a smooth 1.8-2.6 ;x thick wall, spherical (20-60 [x 

 in diameter), oval (20-72 by 30-85 [x), pyriform (20-28 by 40-60 \x), 

 oblong, elongate, or irregular, with one or two nearly sessile exit 

 papillae or discharge tubes, 10^26 by 15-204 [x; rhizoids for most part 

 emerging from several places on the sporangium, the main axes usually 

 coarse, attaining a diameter of 12 [x, irregularly constricted, with thick 

 walls, much branched and extensive; operculum surmounting the dis- 

 charge papilla or just beneath the apex, no hyaline plugs formed, 

 shallowly convex, up to 17 ;x in diameter; zoospores hyaline, spherical, 

 either 5.5-6.0 ;x or 2.0-3.5 ;x in diameter (in same sporangium) with a 

 single hyaline, refractive globule 2.3-2.8 \x in diameter, upon emergence 

 forming a temporary globular mass in a slimy matrix; resting spore 

 not observed. 



Saprophytic on cellulosic substrata in soil and water, United States. 



Similar to Karlingiomyces granulatus and K. lobatus in having endo- 

 and exoopercula and constricted rhizoids, but differing from them in 

 possessing a single large hyaline refractive globule in the zoospore and 



