146 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
THE STRUCTURE OF CERTAIN NEW HYBRIDS (PASSIFLORA, 
ALBUCA, RIBES, BEGONIA, &c.). 
3y Jonn H. Witson, D.Sce., F.R.S.E., St. Andrew’s University. 
THE prediction made by Sabine, in 1820, when describing the first known 
hybrid Passion-flower,* that “the production of plants of a similar 
description will probably be great hereafter,’ has been amply fulfilled. 
The number of hybrids is now very considerable, and their diversity 
bewildering. It is not my intention, however, to attempt to describe, or 
even to compile a new list of, all Passion-flower hybrids. The following 
notes must necessarily be restricted to an account of my own experiments 
at St. Andrews, and to the description of the few hybrids I have been 
able to raise there. 
PASSIFLORA BUONAPARTEA X P. CH RULEA. 
My earliest experiment succeeded admirably, it being the application 
of the pollen of P. cerulea to a flower of P. Buonapartea.r The fruit 
held and ripened. A little further out on the same branch another flowe r 
received pollen of P. Constance Elliot, a variety of P. cerulea, but in 
this case the fruit fell before it was fully developed. I do not possess 
exact measurements of the fruit secured, but I understand that it was 
not so large as the fruit of P. Buonapartea when fertilised by its own 
pollen. It was plump, and contained 370 seeds, the majority of which 
looked healthy. They were sown in my absence, and their welfare care- 
fully attended to, but only one germinated. I believe that a reasonable 
time was allowed for others to appear before the soil was thrown out. 
This solitary seedling grew vigorously, and produced its first flower in 
May 1892. A figure and description of the new hybrid, under the name 
P. Margaret Wilson, are givenin the Gardeners’ Chronicle, vol. xxv. 
srd ser., 1899. 
Comparison of the hybrid P. Margaret Wilson with its Parents. 
The following abbreviations will be used :-— 
B. = P. Buonapartea. 
C. = P. caerulea. 
M.W. = P. Margaret Wilson. 
STEMS. 
The young stem and branches of B. are stout, tetragonal, winged, 
light green. 
* Trans. Hort. Soc. vol. iv. p. 267. 
+ This Passion-flower is stated to be itself a hybrid between P. qwadrangularis 
and P. alata. I have had some difficulty in satisfying myself that it is distinct from 
P. quadrangularis. It would seem that there are varieties of the latter in cultivation, 
some of which are almost identical with P. Buonapartea. It may be remarked that 
P. alata and P. quadrangulavris are often confused in collections and nurseries. Very 
probably seedlings of both, differing more or less from the types, are often cultivated, 
and hybrids between them, other than P. Buonapartea, may also be grown under 
specific names. 
t The description of the microscopic structure of these and other organs is reserved. 
