ACHLYA 131 



17. Achlya conspicua n. sp. 



Plates 45 and 46 

 Hyphac long and more stout than in most Achlyas, up to i66;j. 

 thick near base or some as small as 30^1, the tips often withering and 

 the hyphae extended from a bud below as in A. imperfecta, etc. 

 Sporangia abundant, secondary ones plentiful, varying from short and 

 slender to very long and slender, or rarely stocky when short, 18-60 x 

 l05-550yL; spores emptying and behaving as typical in Achlya, 10.5;^ 

 thick." Oogonia not abundant, borne laterally from the main hyphae, their 

 stalks of moderate length, varying from about as long to twice as long 

 as the diameter of the oogonia, or not rarely even longer; oogonia spher- 

 ical or rarely oval, 51-118^1 thick, most about joix, the walls yellowish, 

 not thick, often strongly pitted, the pits varying much in number and 

 about 5.5;jL wide. Eggs 3-30 or more, usually 4-10, with a diameter 

 of 22-29;ji, most about 2511, not filling the oogonium as a rule; rarely 

 maturing and of obscure structure, apparently about like those of .4. 

 apiciilata when in normal condition, but nearly always degenerating im- 

 mediatelv and becoming irregularly filled with large oil drops. Anther- 

 idial branches androgynous or less often diclinous, usually simple, arising 

 near the oogonia from the main hyphae or often from the oogonial stalks, 

 usually one or two, rarely more, for each oogonium; antheridia on all 

 oogonia, cylindrical or long-tuberous, usually touching the oogonia by 

 foot-like projections, at times applied by the entire side; antheridial 

 tubes obvious. Gemmae not peculiar, long, often in rows by the ab- 

 striction of the longer threads, frequently with prongs, emptying as spor- 

 angia under suitable conditions. 



Found four times in Arboretum branch (No. 5 of July 2, 191 7, 

 Xo. 7 of June 29, No. 2 of July 24, 1920, and April 18, 1921). 



The number of pits may vary remarkably in the same culture and 

 even on the same hypha. In culture No. 2 of July 24, 1920, on a termite 

 some of the oogonia in one section of the culture were without any 

 visible pits except where the antheridia touched ; while in the remainder 

 of the culture oogonia with few to many pits were found, both occurring 

 often on the same hypha. 



Another peculiarity is the strong tendency of the oogonial stalk 

 to flare beneath the oogonium so as to be attached by a broad disc, and 

 this is often so exaggerated as to throw the separation wall a third of 

 the way up the oogonium. 



Achlya americana \ar. cambrica (see p. 139) is superficially somewhat 

 like this l)ut is easily distinguished by the smaller and eccentric eggs, 

 which much more nearly fill the smaller oogonia, and by the origin of 

 the antheridia in greater part from the main hyphae. The subcentric eggs 

 place our plant near A. polyandra Hildebrand, as understood by Humph- 

 rey and Pieters, from which it is separated by the less numerous 

 and much less branched antheridial stalks which spring Ijoth from the 



