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XIV. On the Origin and Nature of the Ligulate Rays in Zinnia ; 
and on a remarkable Multiplication observed in fhe Parts of 
Fructification of that Genus. By Mr. David Dón, Libr. L.S. 
Read November 18, 1828. 
Tur ligulate rays of Zinnia consist of a foliaceous, persistent, 
coloured, and highly vascular membrane, with rough, spinously- 
denticulated edges. ‘They are traversed by two principal trunks 
of vessels almost parallel to their margin, which branch out 
into innumerable ramifications through the disk. ‘These trunks, 
which. are Ecoxiucesd of proper and spiral vessels, may be very 
distinctly traced from the limb of the ray downwards along the 
two prominent edges of the ovarium. "The vessels become 
apparent on the withering of the rays, and the beautiful ai 
ment of their ramifications constitute then an interesting object. 
The principal trunks of vessels, thus occupying both sides of the 
lamina, tend to extend them so considerably beyond the centre, 
as to constitute frequently two distinct lobes. ‘The want of arti- 
culation in the tube, visible in the florets of the disk, their con- 
sistence, and the disposition of the vessels, and their ralasicty 
tion,—a disposition which is found p cisely th esa the 
central ovaria, —would seem to prove that the rays of Zin 
are an elongation of the exterior died Seal o of the ovarium, 
which in the centre florets are developed into a species of ee 
leaceous pappus, which is not present’ in the ray florets. | 
peripherical ovaria are frequently triquetrous, and eac 
dges 
