952 AQUATIC PHYCOMYCETES 



hystrix, coll. A. Jessen, Petersen {he. eit.), Greenland; Acrosiplw- 

 nia sp., coll. K. Rosenvinge, A. incurva, Petersen {he. eit.), Eetocarpus 

 sp., Striaria attenuata, Sparrow (1934c: 17, pi. 4, figs. O-S), Den- 

 mark; Eetocarpus granulosus, Jokl {he. eit.), "Adriatic"; Eetocarpus 

 silicuhsus, Sparrow (1936b), United States; Eetocarpus simplex, E. 

 silicuhsus, Eetocarpus sp., Ceramium diaphanum, Aleem (1950d:428, 

 figs. 11-12), France; Spongomorpha sp., Aleem (1953: 8, figs. 13-16), 

 Sweden. 



Further observations are needed to confirm the sexual process 

 preceding the formation of the resting spores. Companion cells were 

 found in both the Danish and the American material. The great vari- 

 ation in the size of the companion cells in the American material 

 particularly needs further explanation. 



Aleem's (1953) material from Sweden differed in having a less 

 rounded sporangium, which bore only a single discharge tube. 



Fragmentary observations on other "Pleotrachelus" -like marine 

 forms have been reported by Sparrow (1934c, 1936b); some of these 

 forms approximate Olpiciiopsis andreei. One, found in Ceramium 

 diaphanum, had spherical sporangia up to 96 \x or more in diameter 

 with ten or more radiating discharge tubes. Another completely filled 

 the egg of a microscopic animal and formed from one to three broad 

 discharge tubes, through which biftagellate zoospores emerged. 



Olpidiopsis feldmanni Aleem 

 C. R. Acad. Sci. Paris, 235: 1250, figs. a-e. 1952 



Sporangium when in the apical cell of the host spherical, 15-30 (35) 

 \l in diameter, when in older parts subspherical or oblong and 30-45 

 (52) [x long by 20-25 \x wide, with a smooth wall and one (rarely 2-3), 

 short, conical, discharge tube 5-10 a long by 2-4.5 [x wide; zoospores 

 rounded or slightly pyriform with a refractive droplet 2-2.5 jjl long by 

 1.5-2 ix wide with two equal, oppositely directed flagella, emerging 

 directly from the sporangium and swimming away; resting spore not 

 observed. 



Parasitic in the marine algae Falkenbergia rujolanosa, Trailliella 



