CHYTRIDIALES 133 



Olpidium intestinum (Braun) Rabenhorst, Flora Europaea algarum, 3: 283. 



1868. 

 Olpidiella endogena (Braun) Lagerheim, Journ. de Botanique, 2: 438. 1888. 



Sporangium strongly subspherical or broadly ellipsoidal, occasion- 

 ally spherical, up to 35 \i in diameter, its longer axis parallel with 

 that of the alga, wall smooth, slightly thickened, colorless, discharge 

 tube long, 5 \i in diameter, arising from the middle or end of the 

 sporangium, narrowly cylindrical, with a pronounced swelling (6.6- 

 1 1 \x in diameter) where it meets the inner face of the algal wall, ex- 

 tending for a variable distance extramatrically and terminating in a 

 funnel-like apex ; zoospores spherical, 3 \x in diameter, with a colorless 

 globule; resting spore spherical, ellipsoidal, or somewhat pyriform, 

 15 [j. in diameter, wall smooth, colorless, of two layers, the outer thicker 

 than the inner, contents with a large oil globule, germination not 

 observed. 



Parasitic in Closterium, Pleurotaenium, Cosmarium, Penium, Euastrum, 

 Tetmemorus, Micrasterias, etc., Braun (be. cit.), de Bary, Pringsheim 

 (in Braun, 1855a: 384), Schroeter (1885: 180), Cejp (1933a: 2, pi. 1, 

 figs. 1-3), Schulz (1922: 147, figs. 85b, 86-90; 1923: 179, fig. 3), Ger- 

 many; Closterium lunula, Archer (1860:215, pi. 11, fig. 5), Great 

 Britain; Spirogyra majuscula, Loscos (in Rabenhorst, 1868:283), 

 Spain; Closterium lunula, Closterium sp., Sorokin (1874b: 4, pi. 1, 

 figs. 1-5; 1883: 31, fig. 35), Russia; Closterium sp., Dangeard (1886a: 

 285), desmids, de Brebisson (1856: 150), France; Cosmarium pachy- 

 dermum, Skvortzow (1925:429), Manchuria; Penium margaritaceum 

 (F. slide No. 2701). Closterium ralfsii var. hybridum (F. slide No. 

 2703), Linder (1947: 242), Canadian Eastern Arctic; Closterium sp., 

 Wolle (1887: 203), Pleurotaenium sp., Cosmarium sp., Sparrow and Barr 

 (1955: 553), United States; Cosmarium depression var. achondrum, 

 Skuja (1948:379, pi. 39, fig. 8). Sweden; Closterium sp., Litvinow 

 (1953: 76), Latvia; Closterium, Penium, Tetmemorus, Cosmarium, 

 Kobayasi and Ookubo (1954b: 572, fig. 14), Japan. 



Sorokin (1876: 63, pi. 3, fig. 1) placed in this species a fungus with 

 an ellipsoidal sporangium bearing a cylindrical isodiametric curved 

 discharge tube. It occurred in great numbers in eelworms, where it 

 was the first of a series of parasites causing an epidemic in his cultures. 



