86 THE AGARICACEAE OP MICHIGAN 



The Friesian arrangement into two main groups is here retained. 

 Other groupings which have been attempted, seem to me to have 

 brought out no clearer relationships and tend only to complicate 

 matters. The main divisions are here considered as subgenera. 

 These have been subdivided into sections, depending on the char- 

 acter of the surface of the pileus, and on the taste. The key includes 

 only the species so far identified from plants gathered within the 

 state. 



Key to the Species 



(A) Milk brightly colored from the first. [See also (AA) and (AAA)], 

 (a) Young gills and milk indigo-blue. 78. L. indigo Schw. 

 (aa) Not indigo-blue. 



(b) Young gills and milk dark red. 76. L. subpurpureus Pk. 

 (bb) Young gills and milk orange. 77. L. deliciosus Pr. 

 (AA) Milk at first white, changing color on exposure to the air, at least 

 on the flesh, 

 (a) Milk becoming lilac or violet-lilac, at least on the bruised flesh, 

 (b) Pileus zonate, 8-12 cm. broad; stem spotted. 75. L. maculatus 



Pk. 

 (bb) Pileus azonate, 3-7 cm. broad; stem not spotted. 74. L. uvidus 

 Fr. 

 (aa) Milk not changing to lilac. 



(b) Milk becoming pinkish-red, at least on the bruised flesh, 

 (c) Pileus chocolate-brown to pale sooty-brown, usually rugose. 80. 



L. lignyotus Pr. 

 (cc) Pileus grayish-brown to isabelline, even. 79. L. fulginosus 

 Fr. 

 (bb) Milk not changing to pinkish red. 



(c) Milk becoming yellow, at least on the bruised flesh, 

 (d) Margin of pileus tomentose-hairy. 

 (e) Stem spotted; pileus straw-color to ochraceous. 60. L. 



scrobiculatus Fr. 

 (ee) Stem not spotted; pileus buff tinged with flesh color. 62. 

 L. cilicioides Fr. 

 (dd) Margin of pileus glabrous or nearly so. 



(e) Pileus azonate, dry or scarcely viscid, some shade of red- 

 dish-brown, 

 (f) Odor strong, disagreeable. 69. L. theiogalus Fr. 

 (ff) Not with marked odor. 



(g) Pileus substriate on margin, fading to isabelline. 88. 



L. isabellinus Burl, 

 (gg) Pileus even on margin, color of L. comphoratus. 87. 

 L. colorascens Pk. 

 (ee) Pileus zonate, at least toward margin, 

 (f) Pileus very viscid when moist, orange-yellow. 86. L. 



croceus Burl. 

 (ff) Pileus subviscid. 



(g) Pileus distinctly spotted-zoned with dull-orange zones; 



milk very acrid. 68. L. chrysorheus Fr. 

 (gg) Pileus faintly zonate; milk tardily acrid or bitterish. 

 69. L. theiogalus Fr. 

 (cc) Milk not changing to yellow. 



(d) Milk becoming greenish on the bruised flesh. 



(e) Pileus dark i live-green, rather rigid, zonate. 59. L. atro- 



virides Pk. 

 (ee) Pileus livid-smoky-gray, azonate. 73. L. trivialis var. 

 viridilactis. 

 (dd) Milk not changing to green or brownish on flesh. 

 (e) Gills stained gray where bruised. 



