CHAPTER X. 



HEDGEHOG FUNGI: HYDNACEAE. 



The plants belonging to this family vary greatly in size, form, 

 and consistency. Some of them are very large, some quite small, 

 some are fleshy in consistency, some are woody, corky ; some mem- 

 branaceous ; and if we include plants formerly classed here, some are 

 gelatinous, though there is a tendency in recent years on the part of 

 some to place the gelatinous ones among the trembling fungi. The 

 special character which marks the members of this family is the pecu- 

 liarity of the fruiting surface, just as a number of the other families 

 are distinguished by some peculiarity of the fruiting surface. In 

 the Hydnacece it covers the surface of numerous processes in the form 

 of spines, teeth, warts, coarse granules, or folds which are inter- 

 rupted at short intervals. These spines or teeth always are directed 

 toward the earth when the plant is in the position in which it grew. 

 In this way the members of the family can be distinguished from cer- 

 tain members of the club fungi belonging to the family Clavariacece, 

 for in the latter the branches or free parts of the plant are erect. 



In form the Hydnacece are shelving, growing on trees ; or growing 

 on the ground they often have a central or eccentric stem, and a 

 more or less circular cap ; some of them are rounded masses, grow- 

 ing from trees, with very long spines extending downward ; others 

 have ascending branches from which the spines depend ; and still 

 others form thin sheets which are spread over the surface of logs and 

 sticks, the spines hanging down from the surface, or roughened with 

 granules or warts, or interrupted folds (see Phlebia, Figs. 193, 194). 

 In one genus there is no fruit body, but the spines themselves extend 

 downward from the rotten wood, the genus Mucronella. This is only 

 distinguished, so far as its family position is concerned, from such a 

 species as Clavaria mucida by the fact that the plant grows downward 

 from the wood, while in C. mucida it grows erect. 



HYDNUM Linn. 



The only species of the Hydnacece described here are in the genus 

 Hydmim. In this genus the fruiting surface is on spine, or awl- 

 shaped processes, which are either simple or in some cases the tips 

 are more or less branched. The plants grow on the ground or on 



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