THE FUNGI WHICH CAUSE PLANT DISEASE 



435 



margin acute to obtuse, isabelline, sterile, undulate or entire; 

 context punky, thin, ferruginous to fulvous, zonate, 3-5 mm. 

 thick, tubes indistinctly stratified, 5-10 mm. long each season, 

 avellaneous within, mouths circular, minute, 4-5 to a mm. edges 

 obtuse avellaneous to umbrinous, becoming darker when bruised: 

 spores subglobose, smooth, light brown, 5-7 fi; hyphse brown, 4-6 ai; 

 cystidia none. 



On water oak and orange in Florida,^^ especially abundant on 

 the former. 



F. sessilis (Murr.) Sacc. 



A variable fungus with wrinkled A'^arnisheJcap and acute margin, 

 found on decaying deciduous trees. Pileus corky to woody, dimidi- 

 ate, sessile or stipitate, imbricate or connate at times, conchate 

 to fan-shaped, thickest behind, thin at the margin, 5-15 x 7-25 

 X 1-3 cm.; surface glabrous, 

 laccate, shining, radiate- 

 rugose, concentrically sul- 

 cate, yellow to reddish- 

 chestnut, at length opaque, 

 dark-brown usually marked 

 near the margin with alter- 

 nating bay and tawny 

 zones; margin usually very 

 thin and acute, often curved 

 downward, often undulate, 

 rarelj'^ becoming truncate, 

 white, at length concolorous : 

 context soft-corky or woody, 

 radiate-fibrous, concentri- 

 cally banded, ochraceous- 

 fulvous; tubes 0.52 cm. 

 long, 3-5 to a mm., brown 

 within, mouths circular or 

 angular, white or grayish-brown, edges thin, entire : spores ovoid, 

 obtuse at the summit, attenuate and truncate at the base, verru- 

 cose, yellowish-broAvn, 9-11 x 6-8 ix; stipe laterally attached, 

 usually ascending, irregularly cylindrical, 1-4 x 0.5-1.5 cm., re- 

 sembling the pileus in color, surface and substance, often obsolete. 



Fig. 309. — F. pinicola growing on dead trunk 

 of western hemlock. After von iSchrenk. 



