ON UNDERGROUND FUNGI. 11 



been known in this country, and are fi-jurcd l>y Sowerby. A small 

 Truffle, belonging to tbe genus Balsamia, distinguished by its small 

 oblong, smooth sporidia, is often rooted up by squirrels under beech 

 trees, the odour, as the name implies, betraying its presence. 



One of the most curious and instructive genera, as throwing nmcli 

 light on the structure of Truffles, is that of Genea, of which we have 

 more than one species in this country. It is, in fact, a Truffle 

 unravelled, as it were, or turned inside out, so as to expose every one 

 of the veins, so that each has a distinct peridium,the whole having one 

 general aperture, instead of all the veins being enclosed within a 

 single crust. It is foreshadowed, perhaps, by those species of Peziza 

 which are more or less subteiTaneous in their mode of growth, as 

 P. geaster, &c. It is, however, to be remembered that the sporidia 

 have no longer the same hyaline appearance, while the structure of 

 the outer coat resembles that of Tuber. In the genus Spharonoma . 

 there is no peridium, and the structure is as near that of Peziza as is 

 conceivable, the hymenium being merely undulated or tuberculated. I 

 might advert to other genera of which we have examples, and of some 

 of which no British species has as yet been discovered, especially that 

 of Picoa which will some day reward researches among bushes of 

 Juniper. Hydnotrya, like Sphcerosoriia, is entirely without peridium. 

 The genus Ehiphoinijces approaches some of the Puffballs, but has asci, 

 and the sporidia, which are perfectly globose, have more than the two 

 usual integumeuts. The genus Scleroderma, however, which is a true 

 Puff ball, is sometimes quite hypogaeous in its mode of gi'owth, 

 especially where the soil is sandy ; and in some parts of Belgium or 

 the United Provinces, where it is very abundant, it is used when 

 young as a substitute for Truffles, of which it is a sorry representative. 

 It is said it is used especially for the Strasburg terrines. It will, 

 however, be more interesting to proceed to others which are 

 more distantly related in structure to the Puffballs. but in 

 which the veins are not resolved into a mass of threads mixed with 

 the dusty spores. One of these, belonging to the genus Melanofjaster, is 

 well known at Bath as the red Truffle, but though so far culinary as 

 to be employed to give a dark colour to the sauce of a salmi, it is 

 quite free from any pleasant aroma, and if largely used it is very 

 doubtful whether it is quite wholesome. When fresh, the odour is 

 powerful enough, and in an allied species which occurs sometimes iu 

 company with the summer Truffle, the smell is quite overpowering, 

 and approaches that of assafoetida. It was known originally as the 

 Musk Truffle. 



The species belonging to the second division, distinguished by the 

 spores being naked and numerous, but most of them of small size, are 

 merely of botanical interest, and may be distinguished a,s false TrajflcK. 

 Melanogaster and Rhizopogon are distinguished by the peridium being 

 traversed by creeping branched fibres. The spores in the former 

 are dark, in the latter hyaline. Though a species of Rhizopogon 

 sometimes occurs abundantly in sandy soils, its odour in age 



