SAPROLEGNIA 7I 



occur on side branches. (3) The oogonial wall in S. dioi'ca has only a 

 few, or Jio pits, in 5. stagtrali's there arc many large pits visible at 80 

 times magnified. (4) The eggs are smaller (12-22. 5ia) than those of 5. 

 dioica (25-30^1). There are no illustrations. 



Saprolegnia spiralis Cornu. Ann. Sci. Nat., Series 5, 15: 10, pi. 6, figs. 

 10-12 and 15-17; pi. 7, figs. 1-4 and 10. 1872. 

 ? Saprolegnia retorla Horn. Ann. Myc. 2: 233, fig. 21. 1904. 



jMindcn thinks he has found Cornu's imperfectly described species 

 and that it is the same as Horn's 5. retorta. Horn's figure is good, but 

 as Minden's description is more complete, we append a translation of the 

 latter (Krypt. Fl. Mark B. 5: 517. 1912): 



"Turf thick, with long, slender threads ii-i6ij. thick, which are 

 more or less crooked or bent and have slightly granular contents. Spor- 

 angia of various shapes, cylindrical, spindleform, spherical, etc., about 

 30-40;j, thick and 200-300ii. long; secondary sporangia few, growing 

 through the old or formed also by cymose branching, oogonia either 

 on the tips of main threads or on short side branches which are mostly 

 bent, or spiral or sinuous; not rarely the oogonia are also intercalary 

 and then elongated; oogonia rarely quite spherical, mostly elliptic or 

 ovate, at times with a blunt extension at the tip, usually with a small 

 basal neck, wall moderately thick, slightly or not at all pitted; on the 

 average 50x65,1, or also for example 38x46;x. _ Antheridia always 

 i:)resent and usually numerous, irregularly cylindric to clavate, touch- 

 ing the oogonium with the entire length or only with their tips, borne 

 on branches which spring either from the stalk of the oogonium or from 

 the main thread, often numerous and much branched, and after ma- 

 turity quickly becoming inconspicuous. Eggs mostly 1-2, seldom 3 or 

 even 4, smooth, spherical or when several more or less elongated, at 

 maturity with one or many, mostly lateral fat drops and therefore more 

 or less plainly eccentric; diameter 26;;. or for example 34x4511. 



"Found in spring in several places near Hamburg, Germany, mostly 

 in company with other species of Saprolegnia. Resembles S. monoica 

 in androgynous antheridia, but differs so clearly in the position of the 

 oogonia, the small number of eggs and the crooked stalks as to be easily 

 distinct. Its identity with 5. spiralis, while not certain, is made very 

 probable by the few eggs, the crooked stalk, and the opinion of Cornu 

 that his plant was near S. monoica." 



Cornu refers to Braun's pi. 5, fig. 22 ('55), as representing his plant. 

 His own figures show only parasitized parts. 



Horn states that in his plant the oogonia are very numerous, un- 

 pitted, 30-75'^ thick; the eggs 1-8 in an oogonium, 20-2511 thick, with a 

 central fat drop. This plant may be different from the one Mindcn 

 describes above. (See note under S. liloralis.) 



