518 MR. JAMES SMALL ON THE 
bilocular ovaries in the typical genus of the order (13) is much more 
illuminating. The vascular supply of the corolla, on the other hand, seems 
to furnish a means of distinguishing between the bilabiate and the ligulate 
types of corolla in certain cases where the distinction is not obvious. 
Tussilago is one of these. The ray florets are very numerous and form 
several rows, enclosing a relatively small number of male dise florets. 
Without a detailed examination of the conducting tissue it seemed possible 
that this was a truly ligulate corolla with the five teeth at the tip completely 
fused or aborted. 
Senecio vulgaris may be taken as a species with a typical tubular floret, 
and a brief description of the conducting tissue of these florets will furnish 
a basis for comparisons. A model of the vascular system was constructed, 
of which fig. 1 is a sketch; the conducting strands of the stamens are 
indicated by thin lines, and those of the ovule and style by dotted lines. 
In fig. 1 the lines by the side indicate the position of the sections with the 
corresponding numbers in fig. 2, and the position of the axis is indicated by 
an arrow. The diagrams in fig. 2 are so orientated that the posterior part 
of the flower is at the left, and the shaded regions in diagrams 5, 6, and 15 
indieate the position of the nectary. The conducting tissue is composed of a 
few vessels and numerous elon ga ted cells with more or less lignified walls. 
A single strand from the receptacle enters the flower and spreads at the 
base of the ovary, giving what may be called the lower distributive centre 
(fig. 2, diag. 1). From this more or less dise-shaped mass ten bundles are 
given of to supply the wall of the ovary (fig. 2, diag. 2) and а single 
bundle to supply the ovule. Towards the top the ten bundles fuse in pairs 
(fig.2, diag. 3), and a little higher up there is a series of anastomoses 
constituting an upper distributive centre (fig. 2, diag. 4). From this centre 
are given off five bundles, which alternate with the fused petals (fig. 2, 
diag. 5), and a short distance above the zone of anastomoses divide tangen- 
tially to supply the stamens and corolla (fig. 2, diag. 6). The staminal 
bundles remain near the corolla bundles within the tissue of the corolla-tube 
until the filaments are differentiated (fig. 2, diag. 7), and they end in the 
connectives (fig. 2, diag. 8). The two bundles of the style are given off 
from the upper distributive centre (fig. 2, diag. 5), and the anastomosing 
of the five main bundles in this region is probably required on account of 
the want of symmetry, five strands dividing to give the two stylar and five 
corolla strands. Trécul (15) finds that in the Ciehorieze the stylar bundles 
are usually inserted upon the lateral bundles of the ovary, but he remarks on 
the variation shown and does not seem to have observed tlie upper and lower 
distributive centres. 
The lower distributive centre can be compared to the region of fusion 
in Parnassia, and the “raison d’être?” of the complications of the upper 
distributive centre is evidently somewhat similar to that suggested by 
