PI. cell. aph. 1 1 . HYMENOTHECEiE. 278. Sistot. 649 
Boletus biennis, Bull. Champ. 333 ; Sowerhy Fungi , 191 ? 
Sistotrema bienne, Persoon Syn. 550. 
On rotten wood and the’ground. 
2. Sistotrema confluens . Confluent sistotreme . 
Thalli gregarious, usually in pairs, white*, pale ; cap 
fleshy, bent, running together; teeth decurrent, whitish. 
Hydnum sublameilosum, Sowerhy Fungi , 112. 
Sistotrema confluens, Persoon Syn. 551. 
In beech woods and fir plantations, on the ground. 
XXXVII. 279. CERRENA. Micheli. Cerrena . 
Stem distinct ; cap semicircular. 
Cerrena cinerea. Grey cerrena. 
Tiiallus tiledlike, corklike; cap semicircular, rough, un- 
derneath grey. 
Boletus uni color, Sowerhy Fungi , 325. 
Sistotrema cinereum, Persoon Syn. 551. 
On trunks of trees. 
XXXVIII. 280. XYLODON. Persoon. Wood-tooth. 
Thallus attached by its back; teeth irregular, cut. 
1. Xylodon quercinum. Oak wood-tooth . 
Thallus bald, pale reddish-grey; teeth thick, irregular, 
cut, slightly tiledlike. 
Hydnum candidum, Bull. Herb. 481. 
Odontia quercina, Persoon Ohs. Myc. 2, 17. 
Sistotrema quercinum, Persoon Syn. 552. 
On dry oak-sticks. 
2. Xylodon digitatum. Fingered wood-tooth . 
Thallus white, diverging; teeth fingerlike, crowded. 
Hydnum paradoxum, Schrad. Germ. 179. 
Sistotrema digitatum, Persoon Syn. 553. 
On trees. 
