26 



CIRCULAR 14 3, U. S. DEPARTMENT OF AGRICULTURE 



This is an extremely variable species. Authors sometimes recognize three 

 varieties, longipes, e-rpansus, and calopus. The variety lotigipe-s is distinguishetl 

 by the extreme length of the stem, expansus by the breadth and expansion of 

 its cap, and calopus, the most attractive variety, by the chestnut-colored stem. 

 The plants are common and abundant, generally growing in large clusters united 

 by the downy hairs of tlie base of the stems. They are to be found on rotten 

 logs or old stumps of various kinds of trees from ]March to November. I>otli 

 caps and stems of young i^lants are reported edible and as possessing a delicate 

 flavor. 



LACTARIUS 



The distingiiishino; feature of the genus Lactarius is the presence 

 of a white or colored milk, especially abundant in the gills. The 

 entire plant is brittle and inclined to rigidity. The fleshy cap is 

 more or less depressed and frequently marked with concentric zones. 

 The gills are often somewhat decurrent, but in certain species are 

 adnate or adnexed, unequal in length, and often forked. The stem 

 is stout, rigid, central, or slightly excentric. 



Species of this genus are generally terrestrial, often of very large 

 size, and occur in considerable number in open woods or thickets. 



Figure 26. — Lactarius indigo. (Edible) 



LACTARIUS DELICIOSUS. DELICIOUS LVCTAKIUS. (P:DIBLE) 



In this species the cap is convex Init depressed in the center when quite youns. 

 finally funnel shaped, smooth, slightly viscid, deep orange, yellowish or grayish 

 orange, generally zoned, margin naked, at first involute, unfolding as the plant 

 becomes infundibuliform ; the flesh is soft, pallid; the gills are crowded, narrow, 

 often branched, yellowish orange ; the stem Is equal or attenuated at the base, 

 stuffed, then hollow, of the same color as the cap except that it is paler and 

 sometimes has dark spots. 



The cap is 2 to 5 inches broad ; the stem is 1 to 2 inches long and 1 inch thick. 



This fungus is distinctive on account of Its orange color and the concentric 

 zones of light and dark orange on the cap and because of its saffron red or 

 orange milk. A peculiarity of the plant is that it turns green upon bruising 

 and in age changes from the original color to greenish. It is widely distribute<l 

 and of common occurrence, appearing on the ground in woods, solitary or in 

 patches, from June or July to October. 



This species has long been highly prized as an article of food and is thought 

 to have been referred to by Pliny. A picture supposed to be this species has 

 been found in a mural decoration in Pompeii. 



LACTARIUS INDIGO. 



INDICIO LACTARIUS. 



(Fig. 26) 



(EDIBLE) 



In this species the cap at first is umbilicate and the margin involute, later 

 depressed or infundibuliform with margin elevated, indigo blue with a silvery 

 gray luster, zonate. fading in age, becoming greenish and less distinctly zoned, 



