766 
Notes. 
of a laminar expansion, the food-materials for sporangial development 
would not be manufactured locally, but brought from a distance. As 
the vascular bundles of the fertile pinnae are often decurrent in the 
petiole for some distance, there are grounds for supposing the reserves 
of the stem to be the source of the requisite substances. In the case 
under consideration these substances may have been present in the 
stem when the rudiment of the leaf was formed, but gradually destroyed 
in connexion with respiratory processes while the plant remained 
packed up and shorn of its leaves. Or perhaps only the supply of 
these materials to the developing leaf was prevented by the previous 
drying of some of the conducting tissues in the stem. 
There is no need to try to explain the production of nothing but 
normal sterile leaves by the other rhizome. It may have previously 
produced no rudiments of fertile leaves, or none sufficiently far 
advanced to determine the form of the pinnae. 
It should be pointed out that, although the production of an 
anomalous leaf immediately after the plant had been subjected to very 
unusual conditions may be a mere coincidence, a series of cultural 
experiments would probably decide the point, and might lead to very 
interesting results. 
L. A. BOODLE. 
Jodrell Labor atroy, Kew. 
THE VASCULAR, STRUCTURE OF THE ‘ FLOWERS ’ OF 
THE G-HETACEAE : — With a view to determining how much nearer, 
if at all, the vascular structure of the ‘ flowers * of the Gnetaceae 
approaches to the more primitive type of the Cycadaceae than do 
the vegetative parts of these plants, I made a careful examination of the 
axes and foliar members of the flowers of all three genera, with the 
following results. 
The bracts (both those of the general inflorescence and individual 
flowers) exhibit practically the vascular structure of the foliage leaves 
of the same plant, viz. a collateral bundle with transfusion-tissue 
fairly well developed occurring in a lateral position. In the bract 
of the female inflorescence of Ephedra distachya , however, I distinctly 
observed a few tracheides of centripetal xylem on the ventral side of the 
bundle, and, as I have noted in other plants, there occurs more 
immediately in the median ventral position a second group of proto- 
xylem, although very slight in amount, belonging to the centripetal 
