CABPOPUTTA. 163 



Praetical Studies.— (a) Search for cup shaped fungi, in the spring, 

 abmit old hot-beds and upon well-rotted barnyard-refuse. The com- 

 mon Cup-fungus of an amber color (Peziza vulgaris) often to be met 

 with in such localities is one of the best for tlie study of spores and 

 spore-sacs. Make very thin sections at right angles to the inner sur- 

 face. This species may be readily preserved in alcohol for future 

 study. 



(J) Collect the bright-red saucer-shaped plants growing in the 

 woods upon decaying sticks and having a diameter of 1 to 4 cm. 

 Make similar sections. 



(c) Collect a few Morels (Morchella esculenta), and make sections at 

 right angles to the surface of the pits which cover its upper portion, 

 for spores and spore-sacs. The Morel, which grows in the woods, is 

 an amber- or straw-colored fungus 10 to 15 cm. high and having an 

 egg-shaped pitted top, 3 to 6 cm. in diameter, borne upon a thick 

 stalk, both stalk and top being usually hollow. The wliole growth 

 above ground (which Is edible) is to be regarded as a spore-fruit. 



339. The Black Fungi (Order Pyrenomyeetes). — The 

 plants of this order are parasitic or saprophytic in habit; 

 their tissues are usually hard and somewhat coriaceous, dif- 

 fering in this respect from the Cup-fungi, which are generally 

 fleshy. In many respects the Black Fungi are much like 

 the Cup-fungi, to which they are doubtless closely related. 



340. A good illustration of the plants of this order is 

 the Black Knot (Plowrightia morbosa) which attacks the 

 plum and cherry. In the spring the parasitic filaments, 

 which the previous year penetrated the young bark, mul- 

 tiply greatly, and finally break through the bark and form 

 a dense tissue. The knot-like mass grows rapidly, and when 

 full-sized is usually from two or three to ten or fifteen cen- 

 timetres long (.8 or 1.2 to 4. or 6. in.), and from one to three 

 centimetres in thickness (.4 to 1.2 in.) ; it is solid and but 

 slightly yielding, and is composed of filaments intermin- 

 gled with an abnormal development of the bark-tissues of 

 the host-plant. 



341. The knot at this time is dark-colored, and has a 



