SAl'ROI.I-.C'.NIA 69 



"The three varieties show an identical arrangement of the oogonia 

 and are distinguished by tlichnous anthcridia, which are either con- 

 stantly present, or are more or less abundant. They show, however, 

 no agreement in the diameter of the oogonia and eggs, or in the thick- 

 ness of the oogonia! wall. According to Fischer's principle of classifica- 

 tion, i. e., from the presence of diclinous anthcridia, we must place the 

 three species [meaning his three varieties] in the neighborhood of 5. 

 dioica, though in this species the diameter of the oogonia is not given: 

 however, in the egg diameter my No. Ill alone comes near, 22-2()\x 

 against 25-30;^ for S. dioica. This is, however, only of limited signifi- 

 cance. Again, the position of the oogonia — here racemed to clustered, 

 terminal or intercalary, simple or in rows — is still another common 

 character that associates the fungi in question. The name given is 

 intended to show the fact that two of these fungi were isolated from 

 the crust of fungi that covered water pipes." 



The following descriptions are condensed from Alaurizlo: 



Saprolegnia crustosa var. I. p. 52. 



Isolated from a varied growth on the thin shell of a freshly caught 

 mussel {Anodonta mitlahilis) and cultivated for a year. Growth dense, 

 2 cm. long. Sporangia as usual. Oogonia racemose or clustered, also 

 intercalary; and also in simple sympodia of 2 or 4; spherical or elon- 

 gated at times, if intercalary; stalk short, straight, of moderate thick- 

 ness, membrane somewhat yellowish, of medium thickness, with pits 

 of medium size that are not numerous; freciuently an upgrowth enters 

 the oogonium from the wall below; diameter of oogonia 3i.5-6o[x or when 

 elongated 33-41 :j. broad by 50-55^1 long. Eggs 4-25, various in size, 

 mostly 19.5-22JL, smallest I2\i; wall moderately thick and yellowish, 

 Anthcridia mostly present, diclinous, coming from a distance, and plenti- 

 fully enveloping the oogonia, not observed to branch. In this jpecies, 

 as in all the species examined by me, conidia are present, in rows or 

 chains, also in complicated sympodia, rarely single, becoming either 

 sporangia or oogonia, or resting. There are also present in the con- 

 idia the tubes from the cross wall below, as in the oogonia. 



Saprolegnia crustosa var. II. p. 53. 



As with 5. furcata and the following \'ariety, this was found in the 

 laj-er of fungi that covered the inside of the outlet pipe of an aspirator. 

 Cultivated for a year. The dense, if rather slender, threads about 1.5 

 cm. long on a mealworm. Hyphae and sporangia not peculiar. Oogonia 

 in racemes and clusters, mostly spherical, 39-104. 5;i. thick, stalks moder- 

 ately slender. The elongated intercalary ones were not measured be- 

 cause so rare; membrane \ery thin and colorless, pits not numerous, 

 moderately broad, not deep; wall yellowish, after long standing in water. 

 Eggs 1-5 in small oogonia, 9-20 in large ones, ij-2j[x thick, almost 

 filling the oogonia, their membrane thick and somewhat yellowish. An- 

 thcridia numerous, diclinous; entire thread-ends break up into antheridial 



