181 
Proceedings of the Wernerimt Society^ 
Dr Brewster laid before the Society a notice respectiDg the 
developement of crystalline structure by Phosphorescence. See 
this Number, p. 171. 
A paper by Mr C. A. Busby was likewise read, containing 
an account of a method of forming parabolic surfaces, by giving 
a rotatory motion to a stratum of fluid. The mechanism for 
this purpose, consists in a combination of the principle of the 
syphon with that of Barker’s mill. The author proposed to 
apply this idea to the formation of mirrors for large telescopes. 
Art. XXXVI . — Proceedings erf the Wernerian Natural His- 
tory Society, 
Nov. 27. 1819. communications from Dr Traill of 
Liverpool were read. The first contained the description of a 
new species of Siraia, resembling the Preacher Monkey of Pen- 
nant. It is common in the forests of Demerary, and .five speci- 
mens were sent to England in 1817, by Charles Edmondston, 
Esq. ; but the species does not appear hitherto to have been de- 
scribed. It is distinguished by the head being black and beard- 
ed ; tail not prehensile, thickly set with black hairs, claviform ; 
the body below is black, but the back is well clothed with an 
ochry-coloured fur. This gives the animal the appearance of 
being furnished with a jacket, and from this circumstance Dr 
Traill proposes to give it the trivial name of sagulata. The 
other communication consisted of the description of a new spe- 
cies of Felis from Guyana, also sent home by Mr Edmond- 
ston. It is nearly allied to the Puma of naturalists. It has a 
long tail; the whole body is spotless, and of a clear reddish- 
brown colour. Dr Traill proposes to distinguish it by the name 
of Felis unicolor. 
At the same meeting, the first of a series of ornithological 
papers, by Dr Fleming of Flisk, was read, containing a minute 
description from nature of the Water-rail, with remarks on its 
habits. 
At this meeting, being the first which had occurred since the 
yisit of Prince Leopold to Edinburgh, it was proposed by the 
