B c 
) 
PRIMULA ELATIOR IN BRITAIN. 193 
VIII. Hybridization of the Primrose and the Oxlip along their 
dividing line. 
The extreme facility with which the Oxlip and Primrose enter 
into hybrid unions one with the other is highly remarkable. 
Naturally, as the two species come in contact only along their 
mutual dividing-line, it is only there that they hybridize ; but all 
along that line the two species produce hybrids in very great 
abundance. 
The readiness with which the two species hybridize is so great 
that, at places along the boundary-line, it is no uncommon thing 
to find a greater number of plants of hybrid origin than of purc- 
bred plants belonging to both the parent species put together. 
Usually, however, it will be found that one species occupies 
chiefly one portion of a wood, while the other species occupies 
another portion, and hybrid plants in greater or lesser abundance 
occupy a more or less intermediate position. Such is very 
markedly the case in Parsou's Grove, a small wood already 
alluded to, near Lavenham, in Suffolk; but the same state of 
things is observable to an equal extent in so many other woods 
along the boundary-line that it is needless to particularize. 
That the plants in question are really hybrids admits, I think, 
of no reasonable doubt. They have not, it is true, been con- 
clusively proved to be so by means of actual experiment ; but 
there exists, nevertheless, a good deal of circumstantial evidence 
of much the same nature (though less definite and conclusive) as 
that which has been proved reliable in the case of experimentally- 
established hybrids between the Primrose and the Cowslip. It 
18 as follows :— 
(a) That they are always more or less intermediate in form 
between the two reputed parents ; 
(6) That they occur everywhere along the common boundary- 
line at which the two reputed parents meet; and 
(c) That they never occur (so far as my observation goes) 
either in the interior of the Oxlip-Area or away from it 
In the Primrose-Country. 
STE to the great abundance of these hybrids, nothing in 
cas On with them is more remarkable than the uniformity of 
‘Tacter Which they present. In spite of the fact that one ot 
