Io8 THE SAPROLEGXIACEAE 



3. Achlya colorata Pringsh.* Sitzungsber. der Akad. der Wissensch. zu 

 Berlin, 1882, p. 855, pi. 14, figs. 12, 15-31- 

 Achlya racemosa var. stelligera Cornu. Ann. Sci. Nat. Bot. 15: 

 22. 1872. 



Plate 32 



Hyphae stout, 25-50[j. in diameter at base. Sporangia long, almost 

 cylindrical, or slightly tapering toward the end, very little or not at all 

 larger than the hyphae bearing them. Spores ii[x in diameter, emerg- 

 ing and behaving as in ^. racemosa. In neither species is any spontane- 

 ous movement shown before encystment. Oogonia varying greatly in 

 size, 4i-90[j. in diameter, rarely as much as loyix, commonly 55-66[a, 

 racemosely borne on short lateral branches and also at times on the 

 tips of main branches; the yellow walls producing short, blunt out- 

 growths in varying number or rarely almost smooth. Eggs mostly 1-4, 

 rather rarely 5 and very rarely 6, 26-391X in diameter, mostly about 

 30-37;x, centric, the wall very thick. Antheridial branches short, arising 

 from the oogonial branches near the basal wall of the oogonium, and, 

 as in the typical A. racemosa, often from the neck-shaped base of the 

 oogonium itself, rarely from the main hyphae. Antheridia 1-4 on 

 each oogonium, commonly 2, short-clavate, usually bent and apply- 

 ing their tips to the oogonium. Gemmae formed at the maturity of 

 the culture in large numbers. They are scarcely enlarged sections of 

 hyphae arranged in rows of rarely over 5, one erid often projecting 

 to one side below the partition and somewhat thickened. They do 

 not form all the way to the substratum, but only near the ends of the 

 hyphae. When brought into fresh water they sprout by tubes or be- 

 come sporangia. 



Not rare in winter and spring in branches, outlets of springs, etc., 

 as in Arboretum spring and brook, and branch by Raleigh road beyond 

 cemetery. Collected 29 times before December 15, 1913 (see table), and 

 many times since. For other illustrations see Pringsheim ('73). P'- I9. figs. 

 1-15; pi. 21, figs. 1-3 and 13; pi. 22, figs. 1-3; Pringsheim ('83a) pi. 7, figs. 

 10-20; Hine ('78), pi. 6, figs. 1-14; Humphrey ('92), pi. 19, figs. 96-98; 

 Petersen ('10), fig. 3d. 



This good species has been masquerading since its first discovery 

 as a variety or form of A. racemosa, and Fischer (Rabenhorst's Flora, 

 p. 351), finding papillate and smooth oogonia on the same thread, con- 

 siders it the same as A. racemosa. It is true that smooth or nearly 

 smooth oogonia may appear rarely in this species, but they are not the 

 oogonia of A. racemosa, which are always easily recognized by their 

 much smaller eggs. We have never seen a perfectly smooth oogonium 



♦This name was first used by Pringsheim in a footnote in 1874 (Jahrb. f. wiss. Bot. 

 9: 205) as a name he was using in his notes. In the body of the paper and in the plates 

 he still uses A. racemosa. 



