* 
Ir will be eeaihly porrinlid that. the plan, ahen which. 
this volume was begun, has been confiderably contra&ted. To illuftrate 
all the natural orders with an adequate number of medicinal plants, 
which was my original intention, would, as I found upon more fully 
invefligating the fubject, lead to the introduétion of a great many 
vegetables, which, in a medical point of view, might be thought unin 
portant, or entirely ufelefs ;— Influenced by this confi. ideration, and at the 
Jame time finding that the more immediate duties of my profeffion afforded ; 
me but little leifure for profecuting a work of this kind, I did not 
 hefitate to reduce this part to the narrow compafs in which it is here 
prefented.—This volume is therefore rather to be regarded as a Supple- 
‘ment to the three former, than as a Second Part; and more efpecially as 
containing an appendix to the Materia Medica, and the following 
articles admitied into one or both of the collegiate pharmacope@ias, Viz. : 
_ agaricus, angelica fylvefiris, ari iftolochia tenuis, cajeputa, cafcarilla, 
curfuta, laétuca virofa, fantalum rubrum, & citrinum, Seolopendrium, 
and winteranus cortex. 
Ow taking. a 2 final leave of Medical Botany, which owes 
: much of the merit it may poffe of rather to the execution of the artift than 
to the compiler, rg am happy i in the opportunity of acknowledging, with 
gratitude, the favourable manner in which 1 
, piled in oe eae oad, iy medical I gentlemen ia particular. ae 
Aas been received by the ms 
