CLASSIFICATION 443 



every instance the fungus loses a large quantity of water, and 

 shrinks very considerably during drying, becoming rigid and horny 

 when quite dry, but in most instances regains much of its original 

 form and consistency when soaked in water. 



As in every other group of fungi, there is a marked difference in 

 general structure and differentiation l^etween the most primitive 

 and the most highly organized genera included in the group. Taking 

 Dacryomyces and Tremella as representing the simplest types, we 

 find that the whole of the portion commonly considered as repre- 

 senting the entire fungus, consists of hymenium or spore-bearing 

 surface, pointing upwards and not in any way protected. In 

 Dacryomyces the mass is practically even, whereas in Tremella the 

 mass is broken up into numerous plates or folds, thus furnishing 

 a much larger area or spore-producing surface. In Calocera the 

 differentiation of the structure is advanced another step by the 

 assumption of an erect, branching habit, by which the spore- 

 bearing portion of the fungus is elevated well above the substance 

 upon which it is growing, thus affording greater facilities for the 

 distribution of its spores by wind or other agents. The highest 

 type of structure, that is, the modification of an amorphous mass of 

 fungus flesh, as seen in the genus Dacromyces, is met with in Tre- 

 mellodon, where the differentiation into a fertile and a sterile portion 

 is complete. The spore-bearing surface or hymenium is confined 

 to the under-surface of the fungus, by which means it is protected 

 from rain, dust, etc., and is furthermore crowded with spines on 

 which the spores are borne, thus providing a much larger area or 

 spore-producing surface than as if it had been even or more or 

 less wrinkled. 



Owing to the absence of sugar in the tissues, members of the 

 Tremellineae are not attacked by the larvae of insects in the 

 field, consequently, \\'hen collected for preservation they should 

 simply be allowed to shrink until they are perfectly dry and 

 rigid. 



Key to the Genera 

 Broadly attached to the matrix, with the upper part free and 

 reflexed ; hymenium with raised ribs anastomosing to form an 

 irregular network. 



Substance subgelatinous. Auricularia. 



Substance cartilaginous and flexible, ear-shaped, attached by a 



narrow base. Hirneola. 



Cup-shaped, or forming irregular masses, very soft and gelatinous. 



Exidia. 

 Forming brain-like or foliaccous sessile tufts, often quite large. 



Tremella. 



Firm, convex, and more or less plicate, with a central hard, white 



core. Ncsmatelia. 



