146 FUNGUS-FLOEA. 



or at all events in some species whicli hitherto have been 

 considered as belonging to Sydnum. On the other hand, in 

 the genus Odontia the warts or spines are more or less fim- 

 briated or penicillate at the tip. 



Up to the present the genus Porothelium has been included 

 in the Polyporeae, and considered by Tries as having an 

 affinity with, or at all events being analogous to, Fistulina in 

 the distinct warts being at first closed, eventually becoming 

 elongated, and more or less excavated at the apex. This rela- 

 tionship was indicated on the supposition that the hymenium 

 lined the cavities, as in the Polyporeae, but microscopic 

 examination shows that the hymenium covers the outer 

 surface of the warts, as in the Hydneae ; hence Porothelium 

 must be included in the last-named family, and not far 

 removed from the genus Grandinia. 



HYDNEAE. 



Hymenium inferior in the stipitate and dimidiate, hori- 

 zontal species, superior in the effused and resupinate species, 

 bearing from the first spines, teeth, tubercles, wart-like 

 granules, or irregular folds, either entire or more or less 

 fimbriated at the tips ; basidia in most genera tetrasporous ; 

 in one or two ill-understood genera (Knieffia and Mucronella) 

 monosporous. 



Hydneae, Fries, PI. Horn., p. 80. 



The majority of species are effuso-resupinate or entirely 

 i-esupinate, hence the present family is lower in the scale of 

 development of the sporophore than the Agaricineae and the 

 Polyporeae, as in the latter the majority of species are mesopod 

 or central stemmed, whereas the larger number of species are 

 attached laterally, and horizontal — dimidiate. 



ANALYSIS OF TEE GENEBA. 



Hydnum. — Sporophore fleshy, with a central stem or entirely 

 resupinate, texture compact, spines acute, distinct at 

 the base. 



Caldesiella. — Eesupinate; texture floccose, spines acute, 

 spores muriculate. 



