58 DIVISION I. GENERAL MORPHOLOGY. 



hyphae and of their ramifications appears to be entirely without arrangement. 

 R. Hartig's description of Polyporus fulvus should also be consulted \ 



Compound sporophores with distinct pseudo-parenchymatous structure could 

 only be illustrated by a number of individual cases all differing in many points 

 from one another, but such an enumeration would be out of place here. 



One feature common to most, if not all, compound sporophores of all types ot 

 structure is the more or less distinct separation of a peripheral layer from the inner tissue. 

 Compound sporophores with much internal differentiation, among the Gastromycetes 

 especially, exhibit many peculiarities in connection with this point, which will be 

 noticed again in later sections in describing individual cases. The separation" in 

 compound sporophores with progressive growth, and also in some small ones with only 

 slight differentiation, usually consists in the fact that an inner less compact and firm 

 mass, which may be termed the medulla or medullary mass, is surrounded in the parts 

 which do not directly bear the organs of reproduction, as in the sclerotia, by a 

 peripheral rind or cortical layer, in special cases termed also the pellicula or cutis, 

 which is the outer boundary of the whole structure. When the compound sporo- 

 phore forms organs of reproduction directly on its surface, the hymenial layer takes 

 the place of the cortical. Both the medulla and the rind may be separated again 

 into subordinate layers. 



The rind is distinguished from the medulla either by the structure, size, and 

 firmness of union alone of its elements, their arrangement (the fibrillation) being similar 

 in both, or their arrangement also is different. 



In the first case the rind is usually of a firmer texture than the medulla owing to 

 the less breadth and closer union of its elements. This is its character in very many 

 fleshy or cartilaginous Mushrooms, such as the larger Clavarieae, Calocera, many 

 Agaricineae and Pezizeae, and in the stroma of Rhytisma. The cells of the rind have 

 also not unfrequently coloured sclerosed walls, which are wanting in those of the me- 

 dulla, as for instance in Peziza hemisphaerica, Rhytisma, Stereum hirsutum, &c. In 

 other forms the rind is distinguished from the medulla by gelatinous cell-walls, as in 

 the pileus and stipe of Agaricus (Mycena) vulgaris, in the pileus of Russula integra, 

 in Panus stypticus, and many other Agaricineae, the outer covering of which is a tough 

 gelatinous felt, while the interior tissue is not gelatinous. A different arrangement of the 

 elements of the rind from that of the medulla occurs frequently in compound sporophores 

 with hyphal structure ; the hyphae of the medulla follow in their course the form of the 

 sporophore, but numerous curved branches with their convexity towards the apex pass 

 off from its hyphae in the direction of the surface, where they terminate in copious 

 ramifications and close union with one another. The extremities themselves either 

 form a tangled weft, as for instance in Auricularia mesenterica and species of Poly- 

 porus, or else they are placed perpendicularly to the surface, so that the rind appears to 

 be formed of palisade-like cells or cell-rows, as in Peziza Sclerotiorum, in the large- 

 celled tissue of the surface of the stipe of Helvella crispa and H. elastica, in the 

 outer and inner surface of the hollow stipe of H. esculenta and Guepinia contorta 2 , 

 in the smooth surface of the pileus of Polyporus lucidus (Fig. 25), and in that of 

 P. fomentarius. 



1 R. Hartig, Zersetzungserscheinungen d. Holzes, p. 40. 

 * Dacryomyces contortus, Rabenh. Herb. Mycol. Xr. 1984. 



