SAPROLEGNIA 



73 



Found on the egg mass of a snail (Butiyuici) at Hamburg, Germany. 

 It is peculiar in having the sjiorangia spiral or l)ent, in the very large (25;x) 

 spores with a very short and sluggish tirst swinmiing stage, and in the 

 GOgonia being l)orne inside the substratum (egg mass). Oogonia terminal 

 or mostly intercalary, at times many in a row, seldom approaching 

 spherical, mostly only swollen places in the hyphae and very irregular 

 and unsymmetrical with bent in or projecting places in the membrane. 

 Antheridia numerous, borne on long, sinuous, much-branched threads 

 (whether androgynous or diclinous is not stated). Eggs up to lO, mostly 

 3-5, at times only one [size not given]. 



Saprolegnia lapponica Giiumann. Botaniska Notiser, p. 156. 191 8. 



This species is near 5. esocina and S. ferax. As described it differs 

 from the latter in the smaller eggs and in oogonia rarely ever termin- 

 ating the main hyphae. The following is a free translation from the 

 original (there are no figures) : 



"From a puddle at the foot of the Nuolja |Laplandl, I isolated 

 a form which belongs in the 5. Thiireti group, but which cannot be identi- 

 fied with any of the so-far described species. While the typical Thureti, 

 as Fischer correctlj^ obser\ed, has terminal oogonia, those of lapponica 

 are borne laterally and are mostly at a considerable distance from one 

 another and from the ends of the hyphae. The latter can be identified 

 (even \yith the unaided eye) by the pretty turf, in which the oogonia 

 occupying the inner zone cause a white field to stand out; later, in old 

 exhausted cultures, this character is obliterated, in that oogonia may 

 be found farther out and occasionally even terminal as in the typical 

 form. Vet this character of the oogonia being (normally) borne later- 

 ally on the hyphae has remained constant through nine generations. 



"Over against the two other species of the Thureti group, namely, 

 5. esocina and S. bodanica, the demarcation is harder to make good. 

 As to the size of the oospores, 5. lapponica agrees strikingly with S. 

 esocina, in that the majority of the oospores (91 out of 100) are 21-241J, 

 thick. It can readily be separated, howe\-er, from 5. esocina by the 

 brown (not colorless) oosj^ore membrane and by the absence of oogonia 

 in chains. " [Gaumann is mistaken here, for Maurizio says oogonia in 

 chains are not found in his species.] 



"On the other hand .S". lapponica, through its lateral oogonia, re- 

 minds one of S. bodanica. I purposely at this place avoid the expression 

 of a racemose oogonial order, since it could give an incorrect conception 

 of its appearance in regard to 5. monoica. The oogonia are less numer- 

 ous, averaging three to five on each hypha; often situated far apart and 

 occasionally e\en on the same side. W^hile, furthermore, the oogonia 

 of S. bodanica are often borne on long stalks (see Maurizio, pi. 2, fig. 52. 

 1896), in S. lapponica the oogonia are mostly borne on short stalks or 

 are even sessile on the main hyphae. Furthermore, and this is the main 

 point of distinction, the oospores of 5. bodanica measure in general 23.5- 

 31^1, while S. lapponica, as noticed above, vary normally from 21-241X. 



"These grounds caused me to separate the form in question as an 

 individual species, which perhaps may be synonymous with the S. Thureti 



