Harper—Species of Lentinus in Great Lakes Region. 371 
Description of the Groups 
The Lentinus lepideus Group 
Stem central, pilens with large appressed spot-like scales. 
The plants of this group are of medium to large size with lacerate 
serrate lamellae usually sinuate at the base. The pileus and stem 
are coarsely scaly, and the spores are oblong, 3-6 x 8-12/x. The 
sporophores are usually found on wood of coniferous trees. Rail¬ 
road ties and timbers in docks and bridges are especially liable to 
attack. The mycelium is very destructive. The timbers in a dock 
at Neebish, Michigan, were scattered all over with the fruiting 
bodies showing that the wood was everywhere penetrated by the 
mycelium. The plants are usually regular in shape, but many ab¬ 
normal and monstrous forms occur. (See Stevenson 2:155, Sow. 
t. 382; etc.) 
Pileus 2-3 inches broad, fleshy, compact, tough, hard when dry, 
convex or umbonate to depressed, sometimes irregular or eccentric, 
solitary or caespitose, cuticle whitish, pale ochraceous or dark 
brown, breaking up into adpressed, spot-like scales which sometimes 
become blackish. Flesh tough, white. Odor pleasant. Lamellae 
broad, sinuate-decurrent, transversely striate, torn and serrate on 
the edges, white. Stem 1-2 inches long, l/ 2 inch thick, solid, woody, 
often flat or pointed at the base where it emerges from the wood, 
more or less scaly. Annulus near the apex of the stem, more or 
less evident. Spores : ovoid to oblong, 6 x 10/*. Peck 4-6 x 10- 
12y 2 /JL. Stevenson 5 x 11/*. Britzelmayr 3-4 x 20-12/*,. 
On structural timber, usually of coniferous trees. 
1. Plate XIV, A. B. This is the common form with a short stem 
and well marked annulus. The annulus is broad and thick and 
covers the gills in the young carpophore. It is sometimes very 
broad and marked on the upper side with ragged ridges where the 
partial veil was torn from the margins of the gills. 
2. Plate XIY, Z), E. The exannulate form. The stem and 
margin of the pileus are finely scaly, but there is no evident an¬ 
nulus. The plants photographed grew on pine timbers in a side¬ 
walk. 
3. Plate XY, A. A form with slightly scaly pileus, more decur¬ 
rent lamellae, and long, slender stem destitute of an annulus. 
Such forms were associated with others on timbers at Neebish, 
Michigan. The form is Lentinus spretus Pk. (N. Y. State Mus. 
