106 THE AGARICACEAE OP MICHIGAN 



80. Lactarius lignyotus Fr. (Poisonous) 



Monographia, 1863. 



Illustrations: Fries, Icones, PL 171, Fig. 1. 



Michael, Fiihrer f. Pilzfreunde, Vol. II, Xo. 58. 

 Atkinson, Mushrooms, Fig. 110, p. 117. 1900. 

 Hard, Mushrooms, PL 21, Fig. 236, p. 172, 1908. 

 Peck, N. Y. State Mus. Bull. 150, PL 123, 1911. 



PILEUS 3-7 cm. broad, convex, soon almost plane, unibonatc, 

 sometimes slightly depressed and then obsoletely umbonate, dry, 

 azonate, pruinose velvety, even or mostly uneven-rugulose toward 

 the center, chocolate or seal-brown to sooty, margin wavy or sub- 

 plicate in age. FLESH white, slowly pinkish or reddish where 

 wounded,. GILLS adnate-subdecurrent, close to subdistant, mod- 

 erately broad, at first pure ivhite, then ochraceus, reddish or pinkish 

 where bruised. STEM 1-8 cm. long, 1-12 mm. thick, equal or ab- 

 ruptly plicate at apex, pruinose-velvoty. sometimes scarcely velvety, 

 sooty-brown, spongy-stuffed. SPORES globose, 8-9 micr., echinulate, 

 yellowish, sterigmata long. MILK white, changing slowly to red- 

 dish-pink where in contact with flesh, mild or subacrid. Poisonous. 



Gregarious. On the ground in woods, especially in coniferous 

 regions. Marquette, Huron Mountains, Bay View, Ann Arbor. 

 July-September. Infrequent. 



Differs from the preceding in the darker color, the rugose pileus 

 and longer and more velvety stem. Efforts which I made to differ- 

 entiate the two by microscopical characters remained abortive. 

 Both possess slender, cylindrical, aculeate sterile cells on the edge 

 of the gills, about 4 micr. in diameter. The trama of the gills in 

 the specimens examined was more filamentous in L. lignyotus and 

 had a floccose structure of spherical cells in L. fuliginosa. The two 

 species, however, appear to run into each other at times. 



81. Lactarius helvus Fr, 



Syst. Myc, 1821. 



Illustrations: Cooke, 111., PL 991. 



Bresadola, Fung. Trid., PL 127 and 39. 

 Rieken, Blatterpilze, PL 13, Fig. 2. 



PILEUS 4-12 cm. broad, fragile, convex then plane and depressed 



