THE MUSHROOM DIMSION 



503 



Fig. 331. — Field Muslu'oum. .1. vriiical section through part of cap ill) 

 at right angles to gills {I), .^lightly enlarged. B, cross-section through 

 a gill, showing the mass of hyphiB (0 continuous with that of the cap, 

 the spore-bearing layer or hymeniuni (hy), and the layer (sh) from 

 which it developes. C, a part of B (*;"), showing the development 

 of dust-spores (s'-s"") upon the tip of projections from swollen hj-pha- 

 tips or basidia, and other swollen tips (paraphyses, q) which form a 

 large part of the h^'meiiiiini but (.io not produce spores. (Sachs.) 



The poR.ics.sio}! iif hasiiUa characterizes the class, in which, more- 

 owr, .sporangia aye entirely lacking and scarcely a trace of any 

 sexual organ has been found. 



184. The mushroom division, fungi in general, arc most 

 fittingly named after a typo which has departed as far as 

 jiossible from the holophytie condition. 



In trj'ing to coiicei\-e by wliaf course the higher fungi have evoh'ed, 

 naturalists encounter a peculiar difficulty, for although algte of 

 some sort are presumably the starting point of all, the hysterophytic 

 mode of life soon obliterates almost every peculiarity characterizing 



