=nigricans=, Fr. P. 7-12 cm. exp. umbilicato-depr. whitish, soon sooty-olive, flesh white, reddish when broken; g. rounded, very thick and distant; s. 3-6 cm. stout, solid, pallid then black; sp. 8-9. Every part black when old. =adusta=, Fr. P. 6-9 cm. exp. depr. white then brownish, at length scorched; g. thin, crowded, pallid; s. 3-5 cm. solid, pallid then dusky grey; sp. 8-9. Differs from _R. nigricans_ in much closer gills, and in flesh not changing to red. =densifolia=, Gillet. P. 3-9 cm. convex then depr. white then brownish, flesh red when broken; g. thin, crowded, pallid; s. 3-5 cm. slightly mealy, white then grey, at length blackish; sp. 7-8. Differs from _R. adusta_ in flesh turning red, and from _R. nigricans_ in crowded gills. =delica=, Fr. White. P. 8-14 cm. exp. umbil. polished, edge incurved, even, glabrous; g. decur. thin, distant, white; s. 3-5 cm. solid, compact; sp. 8-10 x 6-7. This species has been confounded with _R. chloroides_, Bres. (= _R. delica_, Mass. Fung. Fl. III, 53, _Lact. exsuccus_, Otto, &c.) but differs in polished pileus, pure white gills, &c. =chloroides=, Bresad. (= _Lact. exsuccus_, Otto; _Agaricus chloroides_, Krombh.; _Russula delica_, Mass, &c. not of Cooke). P. 8-12 cm. depr. edge involute, whitish, pubescent, flesh thick, white; g. decurrent, white with a tinge of green, connected by veins, forked; s. 3-5 cm. stout, white, tomentose, sometimes with a pale green zone at apex; sp. 8-9. Differs from _R. delica_ in pubescent pileus and stem, and green tinted gills. ++ _Pileus clear yellow._ =citrina=, Gillet. P. 4-6 cm. slightly viscid, convex then depr.; g. broadest in front, forked, white; s. 4-7 cm. white, solid, slightly rugulose; sp. 7-8. =fingibilis=, Britz. P. 4-5 cm. exp. depr. even, slightly viscid; g. almost free, white; s. 3-5 cm. white, becoming hollow; sp. 7-9. +++ _Pileus greenish or olive._ =olivascens=, Fr. P. 5-8 cm. exp. umbil. olive disc becoming yellowish, edge even; g. white then tinged yellow; s. 2-4 cm. stout, firm, even; sp. 9-10. =heterophylla=, Fr. P. 5-8 cm. exp. depr. even, polished, greenish, yellow-brown, &c., disc becoming ochre, flesh white; g. very narrow, closely crowded; s. 2-3 cm. solid, white; sp. 7-8. var. _galachroa_, Fr. P. milky white then greenish. Differs from _R. cyanoxantha_ in very narrow, crowded gills. [=smaragdina=, Q. P. thin, viscid, somewhat zoned, clear green, edge white; g. narrow, white; s. slender, pruinose, white; taste mild. =azurea=, Bres. P. 4-5 cm. exp. depr. pale glaucous green, with white bloom; g. pale cream colour; s. 2-3 cm. white, rugulose; sp. 8-9. Differs from _R. cyanoxantha_ in white meal on the pileus. =virescens=, Fr. P. 7-12 cm. exp. umbil. dingy opaque green, innately flocculose, areolately cracked; g. rather crowded, forked; s. 4-6 cm. stout, white; sp. 8-9. Edible.