24 GENERAL CONSIDERATIONS 



Fig. 6. Gill trama — parallel type, hyphal cells short and relatively narrow, as found 

 in H. coccineus. See also Fig. 5. 



between the context and the hyphae at the surface. The surface 

 hyphae are repent and often extend in a periclinal direction. At times, 

 even in so-called glabrous pilei, free hyphal ends may extend more or 

 less upward ( Fig. 7, e,g ) . Such an undifferentiated type is not uncom- 

 mon in the section Hygrocybe, especially series Coccinei. A pileus with 

 this type of surface-covering may be moist and hygrophanous, or ap- 

 pressed fibrillose. It becomes squamulose at times if exposed to bright 

 sunlight or dry winds. Most members of the Agaricales showing a 

 similar cutis structure behave according to this pattern. Examples of 

 the simple cutis include: H. aurantius, immutabilis, marginatus var. 

 marginatus (Fig. 7), and subaustralis (Fig. 7). 



Type 2. Non-gelatinous but differentiated epicutis: The most im- 

 portant difference between this and Type 1 is that the hyphae forming 

 the surface layer are narrower (often 1.5-4 fx diameter) and more com- 

 pactly arranged, hence they do constitute a distinct layer as contrasted 

 to the first type. The hyphal walls, as far as can be determined by 

 observation in water, KOH, or Melzer's reagent, are of the same com- 

 position as those of the hyphae of the context. They do not swell up 

 and gelatinize in KOH. A pileus with this type of surface has a 



