\/ iCROSCOPIC ( a Mi \( II R5 9 



The question of whether a pileus is glabrous <>r not is usually de- 

 termined with the naked eye or with die aid oi a hand lens and simply 



means that no debris Iroin a broken \<il is present anywhere, and DO 



scales, loose or attached, are present. Bald is the common term which 



might be regarded as a synonym of glabrous. In some speeies. sneli as 



those in the series Hygrocybe, especially //. minlatus, the young pileus 

 may appear glabrous or at the most appressed fibrillose. At maturity, 

 however, the 1 epicutis ol the pileus loosens, the individual fibrils ag 

 gregating into fascicles attached to the cap at the base but with the 

 free ends projecting. Under a lens such a cap appeals to have small 

 scales and is described as squamulose. The tips oi the squamules may 

 assume a color not in evidence anywhere else on the pileus. Such color 

 differences should be noted. 



In a few species of the section HygrophOTUS the pileus surface is 

 more or less glabrous but is radiateh -streaked usually by appressed 

 fibrils of a different color. This condition is described as virgate and is 

 found in such species as H. virgatulus, II. oliraccoalhiis, and //. cinna- 

 rophyllus. This condition may occur under a thick coating of slime. 11 

 no such coating is present and the ends of the fibrils curl up so as to be 

 free, we have the condition described as fibrillose-squamulose. 



Throughout the genus we find species in which the epicutis of the 

 pileus is formed by a layer of hyphae chemically different from those "I 

 the context because their walls gelatinize. This causes the pileus sur- 

 face to be slippery, sticky, or slimy (gelatinous), depending on the 

 thickness of the epicutis and how far the gelatinization has proceeded. 

 In wet weather this change is accentuated to the point where a pileus 

 may actually have puddles of slime on it, or in continued \\ et \\ eather 

 the layer may be washed away completely. If the opposite conditions 

 prevail and the weather is dry, such an epicutis drying down to a hard 

 shiny layer causes the pileus to appear as if varnished. Under these 

 circumstances the pileus is drv to the touch. The most reliable manner 

 to ascertain if an epicutis is made up of gelatinous hyphae is to section 

 it and mount the sections in water (for fresh material) or 3% KOI I (for 

 material that has been dried). If the hyphae of the epicutis are gelati- 

 nous the layer has a translucence quite different from the context 

 beneath it. The greatest hazard to guard against in sectioning a gelati- 

 nous layer is that the layer does not stick to the razor blade. To avoid 

 this hazard hold the piece of tissue in such a way that the cut is through 

 the epicutis into the pileus context. 



In most species of Hygrophorus the pileus margin is even. In about 

 a dozen of those with thin flesh, however, the gills show through the 

 moist cap as radiating lines or strid(\ and such a cap is described as 



