[Vol. 11 

 28 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



a genus of the Thelephoraceae because the spores are bQrne in a 

 whorl at the apex of the spore-bearing cell. Wolf, loc. cit., has 

 presented the morphology and development of P. nigricans and 

 concludes that Protocoronospora is not a Basidiomycete but one 

 of the Melanconieae, a conclusion in which I concur. 



ASTEROSTROMA 



Asterostroma Massee, Linn. Soc. Bot. Jour. 25: 154. pi. 46, /. 

 8, 9. 1889 ; Sacc. Syll. Fung. 9 : 236. 1891 ; Engl. & Prantl, Nat. 

 Pflanzenfam. (1:1**): 122. 1898; Bourdot & Galzin, Soc. Myc. 

 Fr. Bui. 36: 44. 1920. 



Fructifications resupinate, effused, dry, composed of loosely 

 interwoven hyphae, some of which terminate in brown, stellate 

 organs composed of slender rays; basidia simple, with 2-4 sterig- 

 mata; spores hyaline. 



The species of Asterostroma are likely to be referred to Corti- 

 cium unless sections are examined. In sections the brown, stellate 

 organs are conspicuous when viewed with the microscope and 

 sharply separate Asterostroma from other resupinate thelephora- 

 ceous fungi. Similar organs occur, however, in Aster odon of 

 the Hydnaceae and in a species of Lachnocladium. 



Key to the Species 



No colored hyphae present in the subiculum 1 



Some colored hyphae in subiculum 6. A. ochrostroma 



1. Spores becoming echinulate 2 



1. Spores even 3 



2. Stellate organs with unbranched rays as a rule 1. A. cervicolor 



2. Many stellate organs have some rays branched 2. A. muscicolum 



3. Hymenium drying whitish; no cystidia; rays 3^-4^ n in diam- 

 eter ! 3. A. bicolor 



3. Like A. bicolor except that rays up to 130 X 9 n protrude beyond 



hymenium, like setae 4- A- spiniferum 



3. Stellate organs have notably long, slender rays up to 100-150 X 



3-33^ m; fructification not spongy 5. A. gracile 



1. Asterostroma cervicolor (Berk. & Curtis) Massee, Linn. 

 Soc. Bot. Jour. 25: 155. 1889; Sacc. Syll. Fung. 9: 237. 1891; 

 Bourdot & Galzin, Soc. Myc. Fr. Bui. 36: 44. 1920. 



Corticium cervicolor Berk. & Curtis, Grevillea 1: 179. 1873; 

 Sacc. Syll. Fung. 6: 621. 1888. Asterostroma corticola Massee, 

 Linn. Soc. Bot. Jour. 25: 155. 1889; Sacc. Syll. Fung. 9: 236. 



