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prefence or abfence of this involu-* 
entm, in plants of this Order, is fre- 
quently a very ufeful diftinftion; in- 
deed every the moft minute circum- 
ftance is necefiary in order to difcri- 
minate thefe umbelliferous plants, 
which are a numerous tribe and many 
of them very like each other. 
The generic character is : Involucrum re- 
flexed, concave; petala inflexo-cordate; fruit 
oblong, fmooth. Specific character: Stem, 
in the thick part, groved and hairy, a little 
fwoln and purplifh near the joints j Leaves 
proceeding from a fhort fheath. 
The common height of this plant is about 
two feet; but there is one now in the walks 
of Queen's College, that meafures upwards 
of 4 feet, and is more than half an inch in 
diameter at the bottom. Three days ago, 
I met with a fpetimen at the back gate of 
St. John's, ,ttra entire ftem of which was a 
deep purple. The number of radii are ge- 
nerally 7 or 8.: in that which is now grow- 
ing in Queen's walks, one of the general 
umbels -has eleven. You will find a good- 
engraving of the Charophyllum fyfaeftre in 
Curtis. 
There is another Ipecies common in this 
*! king- 
