[Vol. 5 



196 



ANNALS OF THE MISSOURI BOTANICAL GARDEN 



Oregon : White Pine, J. R. Weir, 398 (in Mo. Bot. Gard. Herb., 



16266). 

 Jamaica: Cinchona, F. 8, Earle, 417, N. Y. Bot. Gard., Plants 



of Jamaica. 



9. A. acerinus (Pers.) v. Hohn. & Litsch. K. Akad. Wiss. 

 Wien Sitzungsber. 116 : 804. pi. 2. f. 6. 1907; Bourd. & Galz. 

 Soc. Myc. Fr. Bui. 28 : 352. 1913. 



Corticium acerinum Persoon, Obs. Myc. 1 : 37. 1796; 

 Romell, Bot. Not. 1895 : 71. 1895. Thelephora acerina Per- 

 soon, Syn. Fung. 581. 1801; Myc. Eur. 1 : 152. 1822; Fries, 

 Syst. Myc. 1:453. 1821; Hym. Eur. 648. lS74:,Stereum 



acerinum (Pers.) Fries, Epicr. 



554. 1838; Sacc. Syll. Fung. 6 : 



587. 1888. 



'/ \!i^ V. Fructifications scattered, re- 

 ^'^' B^ supmate, crustaceous, adnate, 



thin, even, white, the margin 

 Fi^. 9 abrupt; in structure 45-80 /i 



A. acerinus. thick, cousistiug of densely ar- 



Vertical section of fructification -, , ,. . , . n i 



showing scattered immature basidia ranged, hyaline, thm-Walled, 



and absence of gloeocystidia, X92; snhprppf hvnhao flhonf 2-^ u in 

 granule-bearing paraphyses after re- ^"^DCreCt nypnae aOOUt ^6 /i in 



moval of the granular matter by diameter, heavilv iucrusted, 

 HCl. X870. . . , ' ^iT 1. -J- X 



rising between the basidia to 

 the surface and terminating in a racemose manner with short, 

 slender branches, loaded with crystalline matter; basidia 

 clavate, 30-45x6 /x; spores hyaline, even, 10-12x6-7 /x. 



Fructifications about 3 mm. in diameter, rarely elongated 

 up to 10 mm. long, 3 mm. broad. 



On bark of trunks of living maple, oak, etc. Vermont to 

 Texas, westward to Missouri, and in Cuba and Mexico. 

 Throughout the year. 



This species may be recognized by its occurrence in scat- 

 tered, small, white, circular or oblong fructifications on the 

 bark of trunks of living white oak, maple, elm, ash, etc. The 

 smaller spores, racemose paraphyses, and absence of gloeo- 

 cystidia are structural characters separating the species from 

 A, seriatus and A. nivosus. Our American collections are 



