NATURAL HISTORY SURVEY 53 



Among leaves in open grassy places in woods, Glen Ellyn. 

 October, 1902. Our plants are very variable both in size and 

 shape, frequently much deformed (on account of recent frosts?) ; 

 pilous pure white becoming pallid, at first even and moist, the 

 cuticle soft, like white kid-leather; sometimes regular in shape 

 and convex with the margin depressed when old, sometimes with 

 the pileus bi-laterally compressed and upturned, frequently un- 

 dulated on the margin; stems usually short, H to 3 cm. long, 

 compressed and flattened in the larger plants. Spores ellipsoid, 

 inequilateral, 7 to 9 x 5 to 6 /*. 



LACTARIUS. 



Hymenophore continuous with the stem;- lamellae unequal, 

 membranaceous, waxy, slightly rigid, milky, acute at the edge; 

 spores white, rarely yellowish, globose. Fleshy fungi, usually 

 growing on the ground, putrescent; pileus .depressed, lamellae 

 adnate-decurrent, often branched. 



Pileus viscid, milk white, acrid , 1 



Pileus not viscid, milk white, acrid 3 



Pileus not viscid, milk dark blue 4 



Pileus viscid or dry, milk mild or very tardily 



acrid 5 



1. Margin inflexed, tomentose-hairy L. torminosus. 



1. Margin inflexed, pruinose L. trimalis. 



2. Pileus reddish flesh-color or reddish-brown. . .L. hysginus. 

 2. Pileus yellowish-brown or sordid, green L. sordidus. 



3. Pileus convex then piano-depressed L. pergamenus. 



3. Pileus becoming infundibuliform L. piperatus. 



4. Whole plant blue L. Indigo. 



5. Milk white changing to sulphur-yellow L. theiogalus. 



.">. Milk white, unchangeable 6 



6. Pileus pruinose or pubescent 7 



6. Pileus glabrous . 8 



7. Pileus dingy-cinereous or buff-gray. L. fuliginosus. 

 7. Pileus yellowish-red or orange- 

 tawny L.hygrophoroides 



7. Pileus buff-color L. luteolus. 



^. Stem 8 to 20 mm. thick L. volemus. 



8. Stem 2 to 6 mm. thick L. subdulcis. 



Lactarius torminosus Fr. 



Pileus convex then depressed, viscid when young or moist, 

 yellowish-red or pale ochraceous, tinged with red or flesh-color, 

 often varied with zones or spots, the at first involute margin per- 

 sistently tomentose-hairy. 



Lamellae thin, close, narrow, whitish, often tinged with yellow 

 or flesh-color. Milk white, unchangeable, taste acrid. 



Stem equal or slightly tapering downward, hollow, sometimes 

 spotted, whitish. 



Spores subglobose or broadly elliptical, 9 to 10 /A. Pileus 5 to 

 10 cm. broad; stem 3.5 to 7.5 cm. long, 8 to 16 mm. thick. 



