50 JOUKNAL OF THE MiTCIIELL SoCIETY \_June 



40. Lactarius subplinthogalus n. sp. 



Plates 31 and 40, 



Cap up to 10.5 cm. broad, usually 3-5 cm., moderately depressed 

 in center, the margin rounded and somewhat irregular, or at times 

 beautifully and regularly crimped ; surface smooth, dull, minutely 

 pruinose when young, scarcely so at maturity, marginal third with 

 rather strong, radial, irregular pleats which extend in from the mar- 

 ginal crimps; color snuff brown, buffy-drab (avellaneous, Ridgway) 

 to pale ochraceous-buff or occasionally even lighter (light buff, Ridg- 

 way j. Flesh about 6 mm. thick near stem, tough, soft, whitish, turn- 

 ing rosy-salmon when cut, odor pleasant. Milk white, acrid, turning 

 a deep rosy-salmon in contact with flesh and gills. 



Gills very distant, somewhat decurrent, but ending abruptly and 

 somewhat rounded at stem, none branching, not veined at cap, full 

 length ones about 1-1.4 mm. apart at margin and 1-1.4 mm. deep. 

 Between these are shorter ones of three lengths and three distinct 

 widths, all bluntly rounded at the inner end. Color cinnamon-buff, 

 turning rosy-salmon when cut. 



Stem usually 3-4 cm. long, but at times up to 8 cm. ; 7-15 mm. thick 

 at cap, tapering slightly downward, smooth, about color of cap or 

 lighter, flesh varying from solid and elastic and not noticeably stuffed 

 in center (of the same firm consistency all through) to distinctly 

 stuffed and sometimes covernous in age. 



Spores (of No. 1835) cinnamon, spherical, covered with strong, 

 blunt spines of varying lengths on the same spore, some 1.5^ long, 

 others shorter, diameter with spines 10-12fi, most about 11/^. 



This species is distinguished from L. plinthogalus by the larger 

 spores, the solid stem, the very distant and deep gills, and the usually 

 larger size of the plant. It is also usually darker than L. pUnthogalus. 



Miss Burlingham considers these plants as coming within the varia- 

 tion range of L. pUnthogalus, and there is no doubt that this species 

 is a very variable one. However, after careful observation of these 

 plants in Chapel Hill, it seems to me that we have two distinct forms. 

 We do not find confusing intermediates, and all our collections can be 

 easily referred to one or the other group. I consider it less confusing, 



