On the Species of the Genus Primula in Essex. 195 
Darwin shows (‘ Forms of Flowers,’ p. 36) that Primroses 
are fairly fertile when protected from insects [? large insects], 
but that the long-styled flowers are, under these circum¬ 
stances, by far the most productive. He also says (Ibid., 
p. 36):—“ It is surprising how rarely insects can be seen 
during the day visiting the flowers, but I have occasionally 
observed small kinds of bees at work; I suppose, therefore, 
that they are commonly fertilized by nocturnal Lepidoptera”; 
and after saying that bees commonly visit the Cowslip, he 
adds (p. 56):—“ The Primrose is never visited (and I speak 
after many years’ observation) by the larger humble bees, and 
only rarely by the smaller kinds ; hence its fertilization must 
depend almost exclusively on moths. There is nothing in the 
structure of the flowers of the two plants which can determine 
the visits of such widely different insects. But they emit a 
different odour, and perhaps their nectar may have a different 
taste.” Now on this point I must again differ somewhat from 
Mr. Darwin, as I have not unfrequently seen humble-bees 
visiting Primroses. A specimen of Anthrophora acervorum in 
the middle of March last visited five flowers growing near 
together in Westley Wood, Saffron Walden; and my friend 
Mr. H. Bichardson, of Newcastle, observed a common large 
banded humble-bee visit four flowers on three different plants 
near together in the beginning of May, 1881; he has also 
seen a bee visit the Hybrid Oxlip. On one occasion, in the 
beginning of March, 1882, I saw a honey-bee pay fourteen 
visits to flowers on four plants growing near one another in 
our garden ; but the insect seemed to have a difficulty in 
reaching the nectar, and rejected many flowers altogether. 
In the first week of April, 1883, I observed three medium¬ 
sized humble-bees (Bombus sp.) visiting freely quite a number 
of Primrose-flowers in Westley Wood; and on May 1st, in 
Hyde Wood, Little Yeldham, the day being very warm, I 
noticed a number of individuals of Antliophora acervorum at 
many flowers. One of these visited the P. elatiori-vulgaris 
many times; another, very unmethodically, visited Primrose 
sixteen times, Violet five, Primrose one, Violet four, Primrose 
nine, and Violet once, after which I lost sight of it. I also 
