lyS Dr. Smith'/ Defer iptiotr ^f 



important fpeciEc ones. If I am not too fauguinc, I have met with 

 as latisfa-6lory a motle of determining fpccics in Mentha by the calyx 

 and flower- ftalks, particularly with regard to the pubefcence of 

 thofe parts and its various dlre£lion. This is molt peculiarly ufeful 

 in the verticiUatc Mints, where it is moft wanted. In one cafe we 

 find the flower-ftalk and bale of the calyx invariably fmooth and 

 naked, the upper part and teeth only of the latter being rough 

 with haiKS pointing upward ^ i» another the calyx is all over clothed 

 with projefliing horizontal hairs j in a third it is covered with hairs 

 which point upward,, and the fiowcr-ftalk with hairs that point 

 downward. Thpfe circumftances appear to me invariable. I have 

 examined innumerable dried as well- as living fpecimens, I have 

 watched' their growth in different foils, always with this particular 

 object in view, and have found no reafon to alter my opinion. I do 

 not fay the hairinefs of thefe parts never varies in degree, but evea 

 in this refpeft it varies much lefs than that of any other part of the 

 plant, except in M. viridisy which is a fpiked fpecies, and it nevcr 

 varies in direftion. The utility of this fource of difcriraination wLll, 

 beft appear when we come to invefligate the vertieillate fpecies. I 

 fhall therefore fay no more upon it at prefent, but proceed to a 

 pradlical illuflration of the whole. 



As this genus is ^o perfe6tly natural that no one can be more fo, 

 it will be beft, after mentioning its effcntial generic character, to 

 n-ive an account of thofe particulars in which all the fpecies agree. 

 This will prevent ulclefs repetitions in the feparate dcfcriptions of 

 each. 



Generic 



