EXPERIMENTS IN HYBRIDISATION, &=. 123 
of leaves, and in h and f of flowers; altogether favouring that ancestor 
as 20 : 12, or 62°5 per cent. 
(14) B. empetrifolia is prepotent in h of spines and in h, f, and «, of 
leaves, while B. Darwinii predominates in f and c of flowers; im all, 
favouring B. empetrifolia as 16 : 14, or 55°35 per cent. 
(15) B. Darwinii is prepotent in f and ¢ of spines and in h, f, and ¢ 
of leaves, while B. empetrifolia predominates inf andc of stems and 
in f of flowers; in all, favouring B. Darwinii as 17:15, or 53:1 per 
cent. 
(16) B. empetrifolia is prepotent in h and f of stems, in ¢ of spines, 
and in f and ¢ of Jeaves, while B. Darwinii predominates in f of spines, 
in h of leaves, and in f and ¢ of flowers; in all, favouring B. empetrifolia 
as 17 : 16, or 51°5 per cent. 
(17) B. Darvwinii is prepotent in f and ¢ of stems, in f of spines, in h 
and f of leaves, and in h and ¢ of flowers, while B. empetrifolia predomi- 
nates in h of spines, in ¢ of leaves, and in f of flowers ; in all, favouring 
B. Darwinii as 19 : 15, or 55:8 per cent. 
(18) B. Darwinii is prepotent all round in h, f, and ¢ of stems, spines, 
leaves, and flowers, yet distinct traces of B. empetrifolia are to be found 
in all the parts. This form is the nearest reversion to the grandparent 
B. Darwinii in the whole batch, favouring that ancestor as 24 : 12, or 
66°6 per cent. 
(19) B. Darwinii is prepotent in h, f, and ¢ of stems, in h, f, and ¢ 
of spines, in f and ¢ of leaves, and in h and c of flowers, while B. em- 
petrifolia predominates in h of leaves and in f of flowers; in all, favour- 
ing B. Darwinii as 22: 14, or 61°1 per cent. 
(20) B. empetrifolia is prepotent in c of stems, in h of spines, and ~ 
in h, f, and ¢ of leaves; altogether favouring that ancestor as 17:12, 
or 58°6 per cent. 
(21) B. empetrifolia is prepotent in f of stems, in h, f, and ¢ of spines, 
in h, f, and ¢ of leaves, and in h of flowers; altogether favouring that 
ancestor as 20: 12, or 62°5 per cent. 
(22) B. empetrifolia is prepotent in h and f of stems, in h of spines, 
in h, f, and ¢ of leaves, and in h of flowers, while B. Darwinii predomi- 
nates in ¢ of stems; in all, favouring B. empetrifolia as 19:18, or 
59°38 per cent. 
(23) B. Darwinii is prepotent in c of stems and in f of leaves; while 
B. empetrifolia predominates in h of spines and ¢ of leaves; altogether 
fairly intermediate (though very different at first sight from the typical 
hybrid) as 14 : 14, or 50 per cent. 
(24) B. empetrifolia is prepotent in h, f, and c of spines and in h, f, 
and ¢ of leaves; altogether favouring that ancestor as 18:12, or 60 per 
cent. 
(25) B. empetrifolia is prepotent in fof stems, in h of spines, and in 
h and ¢ of leaves, while B. Darwinii predominates in h of flowers; in all, 
favouring b. empetrifolia as 15:13, or 53°5 per cent. 
(26) B. empetrifolia is prepotent in h and c of stems, in h, f, and ¢ 
of spines, in f and c of leaves, and in h of flowers; altogether favouring 
that ancestor as 20: 12, or 62°5 per cent. 
(27) B. Darwinii is prepotent in ¢ of stems, in h, f, and ¢ of leaves, 
