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1216 Development of a Dandelion Flower. [December 
but our dandelion could not be made clearly to show it. As forthe 
ovule itself in this case being a lateral outgrowth on the floral axis, 
there can be no question. At present two general views are held 
as to the morphology of ovules. Robert Brown, Van Tieghem, Ce- 
lakovsky and Warming, sustained by Dr. Gray, maintain that the 
“ovules are productions of and borne upon leaves,” and this with- 
out exception. Bessey? carries this view to an extreme in class- 
ing ovules under trichomes, which they surely cannot be if we 
restrict trichomes to epidermal outgrowths, yet the glandular 
hairs of Drosera contain a fibro-vascular bundle. The ovules of 
Orchidez are the only ones with which I am acquainted in which 
the funiculus contains no fibro-vascular bundle, and hence coud 
be referred to trichomes, just as the sporangia of ferns. 
The second view of the morphology of the ovule, the one held 
by Magnus, Rohrbach, Hanstein, Schmitz and sustained by 
Sachs,’ is that the ovule has different morphological significance, : 
“according to its mode of origin and position.” According to : 
this view ovules are produced either on leaves (carpellary) of the 
axis. To the latter origin are referred all those ovules which are 
strictly terminal structures of the floral axis, as those of Typha 
ceæ and Naiadeæ, and also those which arise as lateral a ae 
dages of the axis. To his lateral division of ovules produced on 
the axis, Sachs would refer those of our dandelion and all | et 
posite. The two views, therefore, are in accord in certain COSY 
and at variance in others, and the species under consideration 
of the latter kind. It would be interesting then, if posse 
is either a branch, and its parts the homologues OF | sad 
their order of development disproves, or it is itself a leaf ae 
comes the homologue of the other flower parts. In the œ 
the dandelion it seems impossible that the ovule cam = If 
ered to be produced on the axis as a lateral outgrowth. © 
fibro-vascular bundle from the-axis led directly into te siod 
such a view might be tenable, but it extends upwards om 
carpellary wall, and sends out a branch to the fun i 
real lateral outgrowths on the axis then, as indicated a its 
lateral fibro-vascular bundles, are the two carpellary 
1 Gray’s Text Book, p. 267. 
? Bessey’s Botany, p. 137. 
3 Sachs’ Text-book, p. 504. 
