748 AQUATIC PHYCOMYCETES 



tiating movement within the sporangium and emerging rapidly through 

 the dissolved tip of the discharge tube, movement even, with sudden 

 stops and changes of direction; resting spore not observed. 



Parasitic in cells of Cladostephus spongiosus, Kny (loc. cit.), Great 

 Britain; C. spongiosus, Magnus (1875: 77, pi. 1, figs. 17-20), Heligo- 

 land; Sphacelaria tribuloides, Pringsheim (1855: 153, fig. 25)?, Italy; 

 Sphacelaria cirrhosa, Magnus (loc. cit.), Chaetopteris plumosa, Petersen 

 (1905:452, fig. II, 5-8), Denmark; Sphacelaria cirrhosa, Sphacelaria 

 sp., Seymour (1929), Sphacelaria cirrhosa, Sparrow (1936b: 250, figs. 

 9-11, pi. 1, fig. 3, pi. 2, fig. 5), United States; Chaetopteris plumosa, 

 Sphacelaria sp., Aleem (1953: 8, figs. 9-12), Sweden; Sphacelaria 

 cirrhosa, Feldmann (1954: 133), France. 



On the basis of Sparrow's (1936b) studies of the zoospores, Karling 

 (1943) transferred this species to Anisolpidium. If, as Karling states, the 

 biflagellate spores described by Pringsheim (loc. cit.) do not belong to 

 the fungus, this is a logical procedure. The movement of the zoospores 

 seen by Sparrow was certainly like that noted in other members of the 

 order. 



Observations on American material indicate that the zoospore effects 

 penetration of the cell by means of a tube through which the contents 

 pass. The young thallus often very quickly attaches itself to the nucleus 

 of the host. When cells of the lateral branches are attacked, they soon 

 exhibit pronounced swelling. The fungus was a true parasite and became 

 inactive under abnormal conditions prevailing in the laboratory. 



Anisolpidium ectocarpii Karling 



Amer. J. Bot., 30: 637, figs. 1-21. 1943 



(Fig. 55 J-L, p. 752) 



"Thalli one to five in a cell, single thallus occasionally occupying two 

 cells; spherical, oval, oblong, cylindrical and irregular; transformed 

 directly into sporangia or resting spores. Zoosporangia hyaline and 

 smooth; spherical, 8-17 [j.; or oval, 15-20 \x X 20-28 (j.; or elongate, 

 10-13 [i x 20-35 [a; or cylindrical with concave ends, 15 X 30 jx; or 

 irregular with one to several tapering exit tubes, 3-5 [i < 10-40 [jl, 

 which may open within the host, or end flush with the outer surface of 



