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IOWA ACADEMY OF SCIENCE 
and Hapalopilus gilvus. The additional hosts noted locally are Rhus glabra, 
Populus grandidentata and. various oaks. 
4. PoEONiDULus coNCHiFER (Schw.) Murrill. (Polyporus conchifer Schw., 
Polystictus conchifer Schw.) 
Common on fallen twigs of the elm. (Ulmus americana). 
5. CoRiOLus VERSICOLOR (L.) Quel. {Polyporus versicolor (L.) Fries), Poly- 
stictus versicolor (Fries.) 
This beautiful species is common on almost all our forest trees and shrubs. 
It is one of our worst forest pests and often invades the orchard and ornamental 
plantations. It causes a serious disease of the lilac and affects the wild grape. 
6. CoRioLus NOGROMARGiNATus (Schw.) Murrill. {Polyporus hirsutus Fries, 
Polystictus pergamiuus Fries.) 
Common and variable, on numerous species of dead wood. 
7. CoRioLus PROLiFiCANS (Fries) Murrill. {Polyporus pergamenus Fries, 
Polystictus pergaminus Fries.) 
Very common both as a parasite and saprophyte on Quercus, Betula, Populus, 
and less frequently on other trees. 
8. CoRioLELLus SEPiuM (Berk.) Murrill. {Trametes sepium Berk.) 
Not common, on dead oak both in the forest and in structural work. 
9. Tyromyces semipeliatus (Peck) Murrill. {Polypurus semipeliatus 
Peck.) 
Rare on Salix, upon which it is a wound parasite, gaining entrance through 
dead branches. 
10. Spongipellis unicoloe (Schw.) Murrill. {Polyporus obtusus Berk.) 
This handsome species is not uncommon on oak saplings throughout the. 
county. It is a wound parasite. 
11. Spongipellis occidentalis Murrill. 
This species, originally described from specimens collected on beech {Fagus), 
has been previously reported only from New York. A fine specimen was found 
on a wound of a trunk of Ulmus americana in Fayette. The species is quite 
distinct from the preceding, which it resembles in being a wound parasite. 
The denser pelius, smaller pores, and the brittleness of the later upon drying 
easily separate it from the former species. 
12. Bjerkandera adusta (Wind.) Karst. {Polyporus adustus Fries.) 
A common and variable species which may be either a true parasite or a 
saprophyte. The light colored, imbricate pelius and smoke colored hymenium 
easily separate this species. I have found it on erect trunks grading into a 
pseudo resupinate form which at first would never be taken for this species. 
Common on oak, basswood, birch, etc. 
13. Bjerkandera fumosa (Pers.) Karst. {Polyporus fumusus Fries). 
Much larger and with a lighter colored .hymenium than the preceding species. 
A single collection was made near Fayette on an old elm log. 
14. Hexagonia alveolaris (DC.) Murrill. {Favolus europeaeus Fries). 
Very common on fallen branches and dead twigs of various trees. 
15. Polyporus arcularius (Batch) Fries. 
Common on fallen twigs, buried roots, and stumps of deciduous trees. The 
species is quite variable, although easily recognized by the alveolar pores, 
ciliated margin and palid pelius, a combination of characters unique among 
the northern species of the genus. 
