viii INTRODUCTION. 



Fig. K. Genus 10. Sphceria. 



A Fungus, having numerous fpherical or oblong veficles, regularly 

 arranged under fome part of its furface; which veficles dificharge a dull 

 or powder. There are two diviiions of this Genus, firll, agaric-like, 

 growing on the ground, of a foft filamentous fubflance, having a proper 

 root, volva, ftem, and pileus ; fecond, parafitic, fefiile, or fupported on 

 a pillar, and are generally of an hard, horny, or woody fubftance through- 

 out. The little figures at K. reprefent the Sphceria tuberculoma, and the 

 Sphceria agar icifor mis t a new fpecies, four or five inches high, with a 

 bulbous volvated root, a ftem, and a pileus. This is a very curious plant, 

 and a true non-defcript, as will be feen in its proper place. 



Fig. L. Genus n. Mucor (Mould or Mouldinefs}. 



A Fungus, confifling of a roundifh veficle, fupported on a filament, 

 and containing numerous feeds, affixed to an hair-like receptacle. The 

 figure at L. reprefents the Mucor mucedo, as it grew on the ftalk of a pear, 

 which had a fmall part of the fruit adhering to it, in a putrid ftate. 



Thefe few characters being eftablifhed in the memory, it will be eafy, 

 on fight of a fpecimen, to determine, properly and certainly, to which of 

 the above families it belongs. But the firfl Genus — the Agarics — being 

 very numerou?, and a perplexing fimilarity obtaining between fome of the 

 fpecies, it therefore becomes neceffary to examine with care, the form, 

 texture, number, and fituation of the parts of the plant under review, 

 before we can difcover a certain discriminative, fpecific mark, peculiar to 

 that fpecies, and not to be found in any other; — and till fuch a mark be 

 difcovered, we cannot truly fay, that the fpecies is properly defined or 

 afcertained. I would not here be underftood to mean, that we are to dif- 

 cover a part in every fpecies, which is not to be found in fome other, this 

 in a fimple fenfe is impofiible ; but the diftingu'ifhing mark is to be dif- 

 covered 



