LEPTOMITALES 883 



zoospores laterally biflagellate, sometimes containing prominent refrac- 

 tive globules; antheridium single, cut off from its concomitant branch 

 by a cross wall, forming a conspicuous fertilization tube; oogonium 

 forming a single oosphere which is differentiated into ooplasm and 

 periplasm; oospore with a smooth endospore wall surrounded either 

 by a thick undulate or reticulate exospore wall or a cellular layer, ger- 

 mination not observed. 



Primarily saprophytic on submerged twigs and fleshy fruits. 



SAPROMYCES K. Fritsch 



Osterr. botan. Zeitschr., 43: 420. 1893 



(Fig. 70A-B, p. 890) 



Naegelia Reinsch, Jahrb. wiss. Bot., 11: 298. 1878. Non Rabenhorst, 1844; 



Lindley, 1845; Moritzi, 1846; Regel, 1848. 

 Naegeliella Schroeter, in Engler and Prantl, Natiirlichen Pflanzenfam., 1(1): 



103. 1893. Non Correns, 1892. 



Thallus differentiated into a poorly defined slender or somewhat 

 distorted epibiotic basal cell and, arising from this, a few repeatedly 

 umbellately branched segmented and constricted cylindrical filaments 

 on which are borne the reproductive organs, segments delimited by 

 pseudosepta, the whole anchored to the substratum by a complex of 

 endobiotic branched holdfasts; zoosporangia smooth- walled, either 

 formed in whorls or umbels at the tips of the segments, from which 

 they are separated by septate constrictions, or appearing lateral; 

 zoospores somewhat reniform, laterally biflagellate, emerging upon the 

 deliquescence of an apical papilla, often surrounded by a more or less 

 evanescent vesicle; antheridium either diclinous or androgynous, borne 

 at the tip of a long or short distal prolongation of the segments, apically 

 applied, with a conspicuous fertilization tube; oogonia monandrous, 

 spherical or pyriform, borne in whorls or umbels or on short constricted 

 segments, the contents at maturity differentiated into ooplasm and 

 periplasm; oospore borne singly and loosely in the oogonium, wall 

 thick, rough, germination not observed. 



The two known species are saprophytic on decaying plant materials, 

 especially twigs, in cool pure waters. 



