_Habitat_ & _Distribution_: Found in pine woods, usually solitary or in small groups. Fairly common throughout the British Isles and characteristic of Scots Pine woods. _General Information_: This fungus can be distinguished by the purplish or wine-coloured cap and the gills being pigmented from youth. There is only one other British species of this genus, i.e. _C. corallinus_ Miller & Watling. _Chroogomphus_ is separated from _Gomphidius_ by the flesh having an intense blue-black reaction when placed in solutions containing iodine, and the gills being coloured from their youth. In many books _Chroogomphus_ is placed in synonymy with the genus _Gomphidius_. However, _Gomphidius glutinosus_ (Fries) Fries, _G. roseus_ (Fries) Karsten and _G. maculatus_ Fries all have whitish gills when immature which gradually darken, and their flesh simply turns orange-brown in solutions of iodine. _G. glutinosus_ is uniformly grey in colour and is most frequently found under spruce and other introduced conifers: _G. roseus_ has a pale-pinkish coloured cap and white stem, and grows with pine; _G. maculatus_ grows under larch and is flushed lilaceous at first but becomes strongly spotted with brown when handled. _Illustrations_: Hvass 192; LH 213; WD 83^{a}. [Illustration: Plate 4. Fleshy fungi: Spores blackish and borne on gills] ~Paxillus involutus~ (Fries) Karsten Brown roll-rim _Cap_: width 50-120 mm. _Stem_: width 8-15 mm; height 30-75 mm. _Description_: Cap: at first convex with a strongly inrolled, downy margin, but then expanded and later frequently depressed towards the centre, clay-coloured, ochre or yellow-rust, slightly velvety but becoming smooth or sticky particularly in wet weather and readily bruising red-brown when fresh. Stem: central or slightly eccentric, thickened upwards, fibrillose-silky, similarly coloured to the cap but typically streaked with red-brown particularly with age. Gills: ochre or yellow-brown then rust and finally darker brown, decurrent, crowded, often branched and united about the apex of the stem; easily peeled from the flesh with the fingers and rapidly becoming red-brown on handling. Flesh: thick, soft and with slightly astringent smell and yellowish to brownish but becoming red-brown after exposure to the air. Spore-print: rust-brown. Spores: medium-sized, ellipsoid, smooth, deep yellow-brown and rarely greater than 10 µm in length (8-10 × 5-6 µm). Marginal cystidia: numerous lance-shaped or spindle-shaped. Facial cystidia: scattered and similar in shape to marginal cystidia. _Habitat_ & _Distribution_: Found on heaths and in mixed woods, particularly where birch has or is now growing, or even accompanying solitary birch trees.