48 
Mycologia 
This genus resembles Rhinotrichum in general appearance and 
in structure, but differs from that genus in the production of 
spores. In Rhinotrichum the spores are produced singly on the 
upper divisions of the sporophores, in Oidinm the spores are pro- 
duced in chains. 
Key to the Species 
Spores not over 30 /ix long. 
Pulvinate, spores 10—20 long. 
Effused, spores ii— 30/x long. 
Effused, spores 12-24/4 long. 
Spores much larger. 
1. O. aureum. 
2. O. simile. 
3. O. Murrilliae. 
4. O. megalosporum. 
I. OiDiUM AUREUM (Pers.) Link, /. c. 
? Alysidinm fidvuni Kunze, 1 . c. 
Torula aurea (Link) Corda, Icon. 2; 8. 1837. 
Pulvinate or tufts sometimes confluent, floccose, yellow, tawny ; 
mycelium creeping, septate, sending up erect or suberect sporo- 
phores ; sporophores erect, simple or branched, septate ; spores 
ovoid-ellipsoid, lemon-shaped, colored, 10-12 X 16-20 /x. 
On decaying wood. 
Specimens examined: New Jersey, Ellis, N. A. F. 164/; 
Pennsylvania, Schweinits. 
In all probability Monilia effiisa Peck^^ belongs here. 
2. OiDiUM SIMILE Berk. Jour. Bot. 4: 310. 1845 
Oospora similis (Berk.) Sacc. Syll. Fung. 4: 23. 1886. 
Monilia aiireof iilva Cooke & Ellis Grevillea 8: 12. 1886. 
Effused, forming a dense mass over the substratum, yellow to 
reddish yellow ; mycelium septate, interwoven ; sporophores long, 
simple or branched, septate ; spores in chains, globose or subglo- 
bose to ovoid, colored, variable in size, 1 1-20 X 18-30 /x. 
On decayed wood. 
Specimens examined: Pennsylvania, Snmstine. 
This species resembles Rhinotrichum Curtisii in general ap- 
pearance. Monilia aurantiaca Peck & Sacc.^* is in all probability 
the same as this species. 
Ann. Rep. N. Y. State Mus. 42: 128. 1889. 
“Ann. Rep. N. Y. State Mus. 42: 128. 1889. 
