MUSHROOMS AND OTHER COMMON FUNGI. 3 



can be determined and the presence or absence of a volva demon- 

 strated. Careful notes of prominent features should always be made 

 at the immediate time of collection, as some characters are extremely 

 transient. If the opinion of an expert is required, such notes should 

 accompany the specimens. If possible, several of each species 

 should be collected in order to show variation. The plants should 

 be separately wrapped in paper, paraffin preferred (not tissue or raw 

 cotton) , and all placed in a wooden box if to be sent by mail. 



MORPHOLOGICAL STRUCTURE OF MUSHROOMS AND CERTAIN OTHER 



FUNGI. 



The parts common to most mushrooms and certain other fungi are 

 the cap and the stem. The cap, or pileus, is the apical, fleshy part 

 which on its lower surface bears gills in Agaricacese, pores in Poly- 

 poracese, and teeth in Hydnacese. The stem, or stipe, is present in 

 many genera and is normally central; but it may be abbreviated or 

 wholly absent, in which case the plant is said to be sessile, or resupi- 

 nate if attached by the back, and the attachment may be excentric 

 (not centrally attached) or lateral. The shape of the cap is described 

 as umbilicate when it has a central depression, infundibuliform when 

 funnel shaped, and umbonate when it has a central elevation. The 

 margin may be involute (rolled in) or revolute (rolled out), repand 

 (wavy), etc. 



The spores, the microscopic bodies analogous to seeds, are developed 

 from the hymenium or spore-bearing tissue, which covers the surface 

 of the gills in Agaricaceae, covers the teeth in Hydnacese, and lines 

 the pores in Polyporacese. 



The gills, or lamellse, are the thin, bladelike, radiating structures 

 borne on the lower surface of the cap. Their color is generally 

 determined by the color of the spores. The method of attachment 

 to the stem is various, and they are described as adnate when attached 

 squarely to the stem, adnexed when reaching the stem but not 

 attached by the entire width, free when not reaching the stem, 

 sinuate or emarginate when notched or curved at the junction with 

 the stem, and decurrent when extending down the stem. The gills 

 are said to be attenuate when their ends are narrowed to a sharp 

 point, acute when they terminate in a sharp angle, obtuse when the 

 ends are rounded, arcuate when arched, and ventricose when 

 broadened at the middle. 



In the early stages of development the margin of the cap lies 

 against the stipe. In certain genera, as Amanita, Lepiota, Agaricus, 

 and others, a thin veil is present, uniting the margin of the cap and 

 the stem. This structure, known as the veil, consists of fibers grow- 

 ing from the margin of the cap and the outer layers of the stem. It, 

 or a portion of it, may persist as a firm movable or nonmovable 

 annulus (ring), as in the genus Lepiota, or in the form of remnants 



