462 . Bulletin 315 



largest; membrane covered with needles of calcium oxalate, never dis- 

 solving in water when 3'oung, but does at maturity often leaving a basal 



collar; columella flattened oval, rarely spherical, 

 ordinarily broader than high, breadth 12-30^11 

 sometimes attaining 35^1; spores are ellipsoidal 2 

 by 4/z, hyaline, occasionally a few are globose 2.5 

 by 2.5M. 



Chlam3^dospores (developed in mycelium) 

 solitary or in chains, size and fonn variable; the 

 ovoid or spherical ones are on the average 1 2 by 

 201X, the barrel-shaped 40 by 14/x and ordinarily 

 united in chains. Zygospores formed from cop- 



""f.JSm XS""a! "'^'^^ °f '™ ™^^"^' Karnetes, (2o-)40-so 



columella and collar, x (-60)^1, the exosporcs brownish, covered with 



2j6.6; B, spores, X2j6 6; tubercles 2-3^1 high and truncate. Azvgospore 

 C, shown: g mcihod of for- ^i- i-, ^ . t, i 



mation of zygospores, x frequently and often irregularly developed on 



236.6; B, mature zygo- ^^le ends of solitary hyphce, which continue to 



spore, X 236.6 J J i- ^ 



grow and produce a second azygospore, poly- 

 morphic and always smaller than the zygospore. 



Hab. Isolated from Montenegro soil by Namyslowski; by the writer 

 from the plant-breeding experimental plats of Cornell University, Ithaca, 

 N. Y., April, 191 1. Plant pathology herbarium No. 5,903. 



Description is after Namyslowski's except as to height of hyph^ on 

 bread, diameter of sporangiophores, disposition of the tubercles on the 

 exospores, and size of the sporangia. The author found the culture attain- 

 ing a height of 0.25 cm. on bread; our culture attains a height of 0.5 cm.; 

 sporangiophores are 5-1 4m as against 5-8 /x. Sporangia show m.aximum 

 of 70/x as against 60/i, with the tubercles varying in arrangement from 

 groups to no groups at all. The original description claims groups only. 

 For these reasons the species is emended as given in this description. 



Zygorrhynchus Moelleri Vuillemin, Importance taxinomique de 1' appareil 

 zygospore des Mucorinees. Bui. Soc. Myc. France, 19: 11 7-1 18. 1903. 



Differs from Z. Vuilleminii only in the size of the spores. Spores are 

 ellipsoidal, straight or slightly curved, 3 by 5-7 m- 



We have retained these two species in this work, and leave to the special 

 student of the Mucorineae whether they shall be so considered or whether 

 they are to be taken as varieties of one species. These cultures have 

 been carried on similar media for many months and still retain this con- 

 stancy. 



Hab. Isolated from soil shipped from East Hampton, Long Island, 

 N. Y., October. 1910, by the writer; also in Norway by Hagem. Plant 

 pathology herbarium No. 5,894. 



