DOR 
yellow flower, like thole of the former fort; the 
Italics of this fort have two or three leaves, which are 
placed alternately, and their bafe fits clofe to the (talks, 
thefe are not fo hairy as thofe of the former fort ; it 
flowers about the fame time with that, and the feeds 
ripen well in England. This grows naturally in Por- 
tugal, Spain, and Italy, but is equally hardy with the 
firft, and multiplies in as great plenty ; the root is 
perennial. 
The third fort hath longer leaves than either of the 
former, which are covered with a hoary down on their 
under fide, and are indented on their edges •, the 
ftalks are tingle, and have feldom more than one leaf 
upon each ; thefe grow a foot and a half high, and 
are terminated by a Angle flower on the top, like 
thofe of the former forts. This grows naturally on 
the Pyrenees and Helvetian mountains. It delights 
in a moift foil and a fhady fxtuation, and propagates 
in plenty, either from feeds or by parting the roots : 
it flowers and feeds about the fame time with the 
former. 
The fourth fort grows naturally on the Alps and Py- 
renean mountains •, this hath a perennial root ; the 
leaves are like of the leffer Daify, but longer, 
and not fo broad. The flower grows upon a naked 
foot-flalk, which is near a foot long ; the roots feldom 
fend out more than one {talk ; the rays of the flower 
are white, and very like thofe of the common Daify ; 
the difk of the flower is yellow, which is compofed 
of hermaphrodite flowers. 
This plant is preferved in botanic gardens for the 
fake of variety, but the flowers make little better 
appearance than thofe of the common Field Daify, 
only they Hand upon much taller foot-ftalks. It 
muft have a fnady fituation and a moift foil, other- 
wife it will not thrive in this country ; it is propagated 
by parting of the roots, for the feeds do not ripen 
well in England. I received this from Verona, near 
which place it grows naturally. 
The roots of the firft fort have been fometimes ufed 
in medicine, fome having commended it as an expeller 
of the poifon of fcorpions ; but others reckon it to be 
a poifon, and affirm that it will deftroy wolves and 
dogs. 
The other forts which have been formerly ranged 
under this genus, are now feparated, and may be found 
under the title Arnica. 
DORSIFEROUS plants [of dorfum, the back, 
and fero, Lat. to bear,] fuch plants as are of the ca- 
pillary kind, without ftalk, and that bear their feeds 
on the backfide of their leaves. 
DORSTENIA. Plum. Nov. Gen. 29. tab. 8. Lin. 
Gen. Plant. 147. [This plant was fo named by fa- 
ther Plunder, from Dr. Dorften, a German phyfician, 
who publifhed a hiftory of plants in folio.] Con- 
trayerva. 
The Characters are. 
It hath one common plain involucrum fituated 1 vertically , 
upon which fit many fmall florets as in a difk \ thefe have 
no petals , but have flour floort fender ftamina , terminated 
by roundiflo fnmmits. In the center is fituated a roundifh 
germen , fupporting a fingle ftyle crowned by an obtufe ftig- 
rna the germen afterward becomes a fingle feed , inclofed 
in the common fiefljy receptacle. 
This genus of plants is ranged in the firft fedtion of 
Linnaeus’s fourth clafs, intitled Tetrandria Monogv- 
rsia, the flower having four ftamina and one ftyle. 
The Species are, 
1. Dorstenia ( Contraytrva ) acaulis, foliis pinnatifido- 
palmatis, ferratis, floribus quadfangulis. Lin. Sp. 
176. Dwarf Dorftenia with many pointed) hd-nd-fhaped . , 
flawed leaves , and flowers placed on a quadrangular re- 
ceptacle. Dorftenia fphondylii folio, dentaris radice. 
Plum. Nov. Gen. 29. Dorftenia with a Cow Parfnep 
leaf) and a I oothwort root. 
2. Dorstenia ( Houftoni ) acaulis, foliis cordatis angula- 
tis acuminatis, floribus quadrangulis. Lin. Sp. 176. 
Dwarf Dorfienia with angular , heart-fhaped , pointed 
leaves , and quadrangular receptacles to the flowers. Dor- 
ftenia dentarias radice, folio minus laciniato, placenta 
DOR 
quadrangular! & undulata. Houft. MSS. Contrayefud 
with a loothwort root) a leaf lefts cut) and a quadrangular 
waved placenta. 
3. Dorstenia (. Drakena ) acaulis, foliis pinnatifido-pal- 
matis integerrirnis, floribus oyalibus. Lin. Sp. 176-1 
Dwarf Dorftenia with many point edy h&nd-fbaped , entire 
leaves , and an oval receptacle to the fiovjers 5 handed 
leaves , whofe angles are very acute , and an oblong four- 
cornered placenta. 
The firft of thefe plants was difcovered by my late 
ingenious friend Dr. William Houftoun, near Old 
Vera Cruz in New Spain. The fecond was found by 
the fame gentleman, on the rocky grounds about 
Campeachy. The third fort was found in great 
plenty in the Hand of Tobago, by Mr. Robert Millar, 
burgeon. But the roots of all thefe fpecies are in- 
differently brought over, and ufed in medicine, and 
for dyeing. 
The firft fort fends out feveral leaves from the root, 
which are about four inches long, and as much in 
breadth ; thefe are deeply laciriiated into five or feven 
obtufe parts, Handing upon foot-ftalks near four 
inches long ; they are fmooth, and of a deep green; 
The ftalk which fupports the placenta arifes from the 
root, and grows near four inches high, upon which 
the flefhy placenta is vertically placed ; this is of an 
oval form about one inch long, and three quarters 
broad. Upon the upper furface of this, the fmall 
flowers are clofely fituated, the flefhy part becoming 
an involucrum to them ; thefe are very fmall, and 
fcarce confpicuous at a diftance, being of an herba- 
ceous colour. \ 
The fecond fort fends out feveral angular heart-fhaped 
leaves from the root, which have foot-ftalks eight or 
nine inches in length and very (lender ; the leaves 
are about three inches and a half long, and almofo 
four broad at their bale, the two ears having two or 
three angles which are acute, and the middle of the 
leaves are extended and end in acute points like a 
halbert ; thefe are fmooth and of a lucid green ; the 
foot-ftalk which fuftains the placenta is nine inches 
long, and about half an inch fquare, and the upper 
furface clofely fet with fmall flowers like the firft. 
The third fort fends out leaves of different forms ; 
fome of the lower leaves are heart-fhaped, having a 
few indentures on their edges, and ending in acute 
points, but the larger leaves are deeply cut like the 
fingers on a hand, into fix or feven acute fegments. 
Thefe leaves are five inches long, and fix broad in 
the middle •, they are of a deep green, and ftand upon 
long foot-ftalks. The placenta is very thick and 
flefhy, an inch and a half long, and three quarters 
broad, having four acute corners ; thefe have a num- 
ber of fmall flowers, placed on their upper furface like 
the other fpecies. 
Thefe plants are at prefent very rare in Europe, nor 
was it known what the plant was, whofe roots were 
imported, and had been long ufed in medicine in 
England, until the late Dr. Houftoun informed us ; 
for although father Plumier had difcovered one fpe- 
cies of this plant, and given the name of Dorftenia 
to the genus, yet he feems not to have known, that 
the Contrayerva was the root of that plant. 
It will be difficult to obtain thefe plants, becaufe the 
feeds are feldom to be found good ; nor will they 
grow, if they are kept long out of the ground ; fo 
that the only fure method to obtain them is, to have 
the roots taken up at the time when their leaves begin 
to decay, and planted pretty clofe in boxes of earth, 
which may be brought very fafe to England, pro- 
vided they are preferved from lalt water, and are not 
over-watered with frefh water in their paffage. When 
the plants arrive, they fhould be tranfplanted each 
into a feparate pot filled with frefh earth, and plunged 
into the bark-ftove, which fhould be kept of a mo- 
derate heat •, and the plants muft be frequently re- 
freshed with water during the fummer feafon ; but in 
winter, when the leaves are decayed, it fhould be 
given to them more fparingly. With this manage- 
ment thefe plants may not only be maintained, bus 
may 
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