the Britifh Species of Mentha. = 15 
fpecies is found capitate and verticillate in the fame meadow, though, 
I acknowledge, no intermediate varieties, by which we could trace 
their connexion, are in general obfervable; but I have feen one or 
two fuch fpecimens. I have ventured to mention this novel opinion 
in the Engli/b Botany, p. 448, and have converfed with feveral ac- 
curate botanifts upon it. Moft of them are fo averfe to it, that I 
cannot venture abfolutely to infift upon it. The following arrange- 
ment of Britifh Mints will therefore be founded on nearly the efta- 
blithed principles of inflorefcence, but I fhall mention wherever thofe 
principles appear to me to divide a real fpecies. 
II. Having found fo much difficulty in determining the fpecies of 
Mentba by all the modes of diicriminaneu. hito contrived, I was | 
{oon convinced of the nece ity of dife | otl ler principle, or 
of leaving the genus together a chien as 1 found it. The expe- 
rienced botanift well knows how peculiarly difficult it is to meet 
with certain difcriminative marks between genera in very natural 
orders 5 happily: it is not always equally difficult in very natural. ge- 
nera to trace out fpecific charaéters. ‘On the contrary, Nature | ge- 
nerally makes fome one peculiar part, either in the herbage or 
flower, fo various in the different fpecies, and fo conftant in the 
fame, as to afford, to a careful inveftigator of the fubject, a very 
certain clue.. Thus, the various ores of the ftamina in Oro- 
banche, the ribs of the calyx in Arenaria, the form of the ftigma in 
Crocus, the. abíence or prefence ofa neétarium. in Gufcuta, the fhape: 
of the cap: fale in- Fumaria: and fome fpecies of Funcus, and its fituation 
in different Saxifraze, the various numbers of ftamina_ and ftyles in. - 
Polygonum, Phytolacca, Cerafii ium, and feveral other genera ; all tl 
circumftances, fome of which .in other inftances afford generic dit- 
tinCtions, i in the above natural genera conftitute the beft and moft 
Vou . Aa important 
