208 On the Species of the Genus Primula in Essex. 
their seeds, although the new crop of seeds was already 
beginning to form. This habit of the Oxlip is an exceptional 
one, I believe; most plants in this country get rid of last year’s 
seeds before they begin to produce another crop. A shake will 
throw the seeds out of the capsules, and very likely distribute 
them to the distance of a foot or so, where they will have 
a far better opportunity of growing than if the capsules 
were pendant like the flowers and merely threw the seed 
down on to the plant. The clusters of capsules form very 
pretty objects. 
Our three species secrete plenty of nectar, which in hot 
weather may often be tasted on pulling out the corolla. 
They all emit fairly powerful scents, which are much of 
the same kind, yet quite distinguishable. That of the 
Oxlip may be somewhat likened to the smell of peaches or 
apricots. 
The Hybrid Oxlip is easily distinguished from the True 
Oxlip. Its extremely variable nature shows that it is not a 
true species, and Darwin’s elaborate experiments (‘ Forms of 
Flowers,’ pp. 63-70) have proved conclusively that it is a 
hybrid between the Cowslip and the Primrose. It occurs 
more or less commonly in all places where both these grow 
full complement of pollen, the stock of the s. would be much diminished. 
Thus nectar-seeking insects which effect cross-fertilization would neces¬ 
sarily carry more long-styled pollen to s. than short-styled pollen to L, 
and consequently the chances of the s. being cross-fertilized would be the 
best. Also, inasmuch as the majority of fertilizations would be the result 
of the action of long-styled pollen upon the ovules of s., it is conceivable 
(assuming the prepotency of the male element in plant-fertilization) 
that the “ long-stylism ” of the pollen would be impressed upon the 
resulting seeds, leading eventually to a slight increase in the number 
of 1.; while, owing to the “artificial” selection by pollen-gatherers, as 
above indicated, the s. would produce the greater quantity of seeds. 
In this way also we may explain the discrepancy between Mr. Darwin's 
and Mr. Christy’s observations. If our hypothesis be true, the relative 
numbers of the two forms in any given locality would depend very much 
upon the presence or absence of species of pollen-gatliering bees. In 
places where these insects are common, 1. would tend to increase; but 
where they are rare or absent the numbers of the two forms would become 
equalized, owing to efficient reciprocal cross-fertilization by nectar¬ 
seeking bees.— Ed.] 
