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LXV. Some Obfervations upon the Sleep of 
Plants \ and an Account of that Faculty , 
which Linnaeus calls Vigilias Florum ; with 
an Enumeration of fever al Plants , which 
are fubjeB to that Law . Communicated 
to Wm. Watfon, M. D. F. R . S. by Mr. 
Richard Pultney of Leicefter. 
Read Jan. 26. yi Cofta and Profper Alpinus, who both 
*758. f\ wrote near the conclufion of the 
XVIth century, are, I believe, the firft, who recorded 
that nocturnal change in the leaves of plants, which 
has fince been called fomnus . It is an obfervation 
indeed as old as Pliny’s time, that the leaves of tre- 
foil aflume an ere£t fituation ( 1 ) upon the coming of 
ftorms. The fame is obfervable of our wood-forrel ; 
and Linnaeus adds, of almoll all plants with de- 
cimated flamina (2). In the Trifolium pratenfe al- 
bum C. B. or common white-flowered meadow tre- 
foil, it is fo obvious, that the common people in 
Sweden remark, and prognofticate the coming of 
tempefts and rain from it. 
The examples of Deeping plants inftanced by Al- 
pinus are but few. That author fays, it was com- 
mon to feveral Egyptian fpecies (3) ; but fpecifies only 
the Acaciae, Abrus, Abfus, Sefban, and the Tamarind- 
(1) Trifolium quoque inhorrefcere et folia contra tempeftatem 
fubrigere certum eft. Hift. Nat. lib. xviii. cap. 35. 
(2) Flor. Lappon. p. 222. 
(3) Profp. Alpin. de plantis flSgypti, cap. 10. 
tree. 
