LACTARIAE ОЕ THE UNITED STATES 19 
Pileus fleshy, compact, convex-umbilicate, at length infundib- 
uliform, white, azonate, dry, glabrous, 4—12 cm. or mere in diam- 
eter, margin involute at first and naked, at length uplifted; gills 
white or creamy-white, forking dichotomously, close, more or less 
decurrent, arcuate at first, then extending upwards, only about 2 
mm. broad ; stem white, equal, dry, often pruinose, solid and firm, 
2-8 cm. long, up to 2 cm. thick, flesh white, unchanging or 
becoming sordid ; spores white, subglobose, nearly smooth, 8-0 и; 
latex white, unchanging, very acrid, abundant. Ва. 
Has.: In oak woods or groves. July to October. 
DISTRIB.: New York, Peck, Earle, Burlingham 20, 1905; 
Connecticut, Underwood; New Jersey, Sterling ; Pennsylvania, 
Mrs. Dallas; Maryland, Banning ; District of Columbia, Murrill, 
1403; Virginia, 600 meters elevation, Murrill 272 and 377; 
North Carolina, Burlingham,; South Carolina, Ravenel; Tennes- 
see, 500 meters elevation, Murrill 517 В; Alabama, Underwood ; 
Indiana, С. W. Wilson; Missouri, Glatfelter 345. It has also 
been reported from the following states: Maine (White) ; Vermont 
(Frost); Rhode Island (Bennett); Ohio (Morgan); Minnesota 
(Johnson); Wisconsin (Bundy) ; California (Harkness & Moore). 
Плозт.: Atkinson, Stud. Am. Fungi, /. 119; Banning, Folio 
Md. Fungi, ai 83 ; Вапа, Champ. Nice, £l. 22. f. 1-5 ; Bel. Champ. 
Tarn. ai 22; Bern. Champ. Roch. AX. 57. f. 2; Bolt. Geschichte, 
pl. 21; Boyer, Champ. Comest. е: Ven. Fr. p/. 30; Britz. Lact. 
f. 24; Bull Herb. Fr. pl. 200, Agaricus acris; Cooke, Br. 
Fungi, ai 979; Cordier, Champ. Fr. pl. 28. f. г; Eng. & Prantl, 
Nat. Pflanzenfam. 1'**: 7 110В; Fl Dan. M. 1132; Fries, 
Sverig. Svamp. р/. 27; Hahn, Der Pilz-Sammler, f. 19, ed. 2; 
Harzer, Pilze, ai 39; Krombh. Abbild. ai 56. f. 1-4; Lanzi, 
Fung. Mang. AM. 54. f. 2 a, 6, c; Lorinser, Essb. und Gift. 
Schwàm. A. о. f. 4; Mcllvaine, One Thous. Am. Fungi, ai 47. 
f. 1.; Pat. Tab. Analyt. Fung. A. 110; Paulet, Traité Champ. 
pl. 68. f. 3-2; Roumeg. Crypt. Illustr. Æ 144; Rich. & Roze, 
Atl. Champ. AX. 40. f. 5-8 ; Schaeff. Fung. Bav. Icon. AM. 83, 
Agaricus amarus; Sicard, Hist. Nat. Champ. ai 44. J. 225) 
White, Conn. Geol. and Nat. Hist. Surv. Bull. 3: ai 9. 
Exsic.: Ravenel, Fungi Caroliniani, fasc. 2, 5 р. Р.; Roume- 
guére, Fungi Gallici 3679. 
DISTINGUISHING FIELD-MARKS: The glabrous, white pileus, the 
