182 THE NORTH AMERICAN SLIME-MOULDS 



color, infests preferably very rotten logs of Quercus, on which in 

 June the sporangia rise as white or pallid columns. The peridium is 

 exceedingly delicate, less seldom seen here than in some other species, 

 but likely to be overlooked entirely. The spores when fresh have a 

 distinct violet or bluish tinge ; in old specimens they are almost color- 

 less. In any case they are well marked by the large papillae already 

 referred to. 



C. typhina, var. hetcrospora Rex, differs from the type in several 

 particulars: the sporangia manifest a closer habit; the capillitium is 

 made up of more slender threads and forms a yet denser network; 

 the spores between the large papillae are marked by a more or less 

 perfectly formed reticulation. ^ 



As to nomenclature, this is our old friend C. typhina (Pers.) Rost. 

 It should be, more properly, called C. typhina Rost., for it is not 

 Persoon's species exactly. But Scopoli, /. c, by citing Hall, Gleditsch, 

 and Micheli, so describes our form as to leave small doubt that he 

 had before him our common species. Schaeffer's figures also come to 

 the rescue, which, though by no means satisfactory, yet can probably 

 refer to no other species. However, Bulliard gives the first good 

 account and figure, and in concord with the decision of our English 

 colleagues, the name afforded by the famous Champignons is here 

 adopted. 



Widely distributed. Maine to California, and from British Amer- 

 ica to Nicaragua. 



11. CoMATRiCHA ELEGANS (Racib.) List. 



Plate XVI., Fig. 12. 



1884. Rostafinskia elegans Racib., Rozpr. Akad. Krak., XII., 77. 



1888. Raciborskia elegans Berl, Sacc. Syl., VII., p. 400. 



1894. Raciborskia elegans Berl., List., Mycet., p. 133. 



1909. Comatricha elegans List., Br. Mus. Guide to Mycet., p. 31. 



Sporangia loosely gregarious, globose, purplish-brown, small, 1-1.5 

 mm. in total height, stipitate; stipe black, subulate, to 1 mm.; colu- 



1 In the Mycetozoa, 2nd ed., p. 158, is cited Stemonitis virginiensis Rex as a 

 synonym of this variety. By reference to p. 163 of the present volume the 

 Virginian stemonitis is left as Rex assigned it, and if the present variety be 

 synonymous, it should be quoted there. The treatment of the species C. nigra 

 in the second edition does not establish such fact, nor with three varieties 

 make for any increasing clearness. 



