CLASSIFICATION. 67 



coat or peridium, which is at first pale, but ultimately becomes 

 brown. Internally is at first a cream-coloured, then greenish, 

 cellular mass, consisting of the sinuated hymenium and young 

 spores, which at length, and when the spores are fully matured, 

 become brownish and dusty, the hymenium being broken up 

 into threads, and the spores become free. In earlier stages, 

 and before the hymenium is ruptured, the spores have been 

 found to harmonize with those of Hymenomycetes in their mode 

 of production, since basidia are p'resent surmounted each by 

 four spicules, and each spicule normally surmounted by a 

 spore.* Here is, therefore, a cellular hymenium bearing qua- 

 ternary spores, but, instead of being exposed, this hymenium 

 is wholly enclosed within an external sac or peridium, which 

 is not ruptured until the spores are fully matured, and the 

 hymenium is resolved into threads, together forming a pul- 

 verulent mass. Ib must, however, be borne in mind, that in 

 only some of the orders composing this family is the hymenium 

 thus evanescent, in others being more or less permanent, and 

 this has led naturally enough to the recognition of two sub- 

 families, in one of which the hymenium is more or less per- 

 manent, thus following the Hymenomycetous type ; and in the 

 other, the hymenium is evanescent, and the dusty mass of spores 

 tends more towards the Coniomycetes, this being characterized 

 as the coniospermous (or dusty-spored) sub-family. 



The first sub-family includes, first of all, the Hypogai, or sub- 

 terranean species. And here again it becomes necessary to re- 

 mind the reader that all subterranean fungi are not included in 

 this order, inasmuch as some, of which the truffle is an exam- 

 ple, are sporidiiferous, developing their sporidia in asci. To 

 these allusion must hereafter be made. In the Hypogai, the 

 hymenium is permanent and convoluted, leaving numerous 

 minute irregular cavities, in which the spores are produced on 



* Berkeley, M. J., "On the Fructification of Lycoperdon, Phallus, and their 

 Allied Genera," in "Ann. of Nat. Hist." (1840), vol. iv. p. 155; "Ann. dea 

 Sci. Nat." (1839), xii. p. 163. Tulasne, L. E. and C., "De la Fructification dea 

 Scleroderma comparee a celle des Lycoperdon et des Bovista," in " Ann. desSci. 

 Nat." 2 me aer. xvii. p. 5. 



