SAPROLEGNIA 55 



irregular in diameter, usually curved, repeatedly proliferating, later ones 

 more irregular and often pointed; spores 10-121J1 in diameter. Gemmae 

 very abundant, spherical, pyriform, clavate, etc., often in chains, the 

 terminal one very often with an elongated papilla. Oogonia plentiful 

 as a rule, about as much so as in Saproleguia ferax, but at times not 

 found on grubs in distilled water (more scattered than in Saproleguia 

 delica and Saproleguia anisospora), about 35-80;!. thick, the larger nimi- 

 ber terminal on main hyphae, others (usually appearing later) on short 

 lateral branches; shape spherical, or if Ijorne on the ends of main threads 

 usually oval, the latter frequently with a slender, more or less lengthy 

 terminal extension, which when short may be included in the cavity of 

 the oogonium, but which is often extended into a thread 2.8-3[x thick, 

 thus making the oogonium intercalary; furnished with rather few, very 

 conspicuous and usually large pits, up to ii[x across. Eggs centric, 

 large and dark, 1-20, mostly 2-6 in an oogonium, their diameter 20~^0\i., 

 most about 30-33yL, often elliptic from pressure. Antheridia on every 

 oogonium (one to several), androgynous on short branches which usually 

 arise very near the oogonium, frequently, when the oogonium is on 

 a short stalk, arising from immediately below it. In addition to the 

 androgynous antheridia a few diclinous ones may arise rarely from other 

 nearby threads. 



We have not found this in Chapel Hill, our only collections having 

 been taken by us in fresh water with algae in a roadside ditch near South- 

 port, X. C. (Xo. 3 of April 6, 1918), and in a ditch at the golf links, Wil- 

 mington. X. C, Dec. 27, 1922. 



There seems little doubt that this is near the European Saproleguia 

 paradoxa of Maurizio* (see p. 75) which agrees in the characteristic 

 antheridial branches and in the apical extension on some of the oogonia. 

 \\'e would refer our plant to this species except for the much smaller eggs 

 and frequent presence of an ingrowing process from below in the oogonia 

 of the latter. 



The present species is obviously near Saproleguia monoica, but is 

 clearly distinct in the much larger eggs, the absence of an ingrowing 

 tube from the oogonial wall below, in the presence of a slender exten- 

 sion on the tips of many of the oogonia and gemmae, and in the typically 

 more abundant and more branched antheridial branches. These latter, 

 when the oogonium is apical on a main thread, may be so abundant and 

 branched as to give the effect of a basket holding the oogonium. It is 

 possible that this is the plant Minden found and describes as S. spiralis 

 Cornu and thinks is the same as S. retorla Horn. If his plant is indeed 

 the same as ours it is not S. retorta, which is easily different, nor does 

 our plant correspond to Cornu's imperfect description of S. spiralis. 



*Not of Petersen, which was published about ten years later: see under A planes 

 Treleaseanus ([). 79). 



