[ 86 7 ] 
at Fulham, to examine his curious colledlion of 
exotic plants, I began with the Rhus, or Toxico- 
dendron, in order to the clearing up fome points 
difputed in two letters, lately published in the latt 
volume of our Tranfadlions, N°. 49, part I. p. 1 57 
to 166. One from the Abbe Mazeas to Dr. Ste- 
phen Hales, on the difcovery of the juice of certain 
fpecies of Toxicodendron Raining linen of a fine 
black colour, and the other in anfwer to it from Mr. 
Philip Miller, of Chelfea, infilling that it was not a 
new difcovery. 
In order to be fatisfied of the fadt ; I made feve- 
ral experiments on the three fpecies of Toxicoden- 
drons mentioned by the Abbe Mazeas ; and find, that 
the juices of them do Rain black, and if fixed by 
a Hum are not to be wafhed out by foap, or boiling 
in a lee of pot-afhes : but the pinnated one called by 
the gardeners the poifon a Hi, did not flrike fo deep a 
black as the other two trifoliate ones, being more of 
a rufly colour. 
I went now upon the enquiry to compare, and 
fee, whether in reality this pinnated Toxicodendron 
of our North American fettlements, is the true var- 
nifh tree of Japan, as afferted by Mr. Miller ; and 
firR I found it neceffary to know, where this poi- 
fon tree was defcribed. This I was led to by Mr. 
Miller’s letter, where he fays, the poifonous quali- 
ty is defcribed in the Philofophical Tranfadtions, 
N°. 367. p. 145- and 146, and a very exadt ( 3) figure 
of a leaf of it therein referred to in Plukenet’s Phvto- 
* 
graphia, Tab. 147 Fig. 1 . 
(1) Fig. t. Tab. 24. 
In 
