Jamaica, where they have long been naturalised, and, on carefully comparing
them under the microscope with my own bees, I could detect not a trace of
difference.

This remarkable uniformity in the hive-bee, wherever kept, may probably be
accounted for by the great difficulty, or rather impossibility, of bringing
selection into play by pairing particular queens and drones, for these
insects unite only during {299} flight. Nor is there any record, with a
single partial exception, of any person having separated and bred from a
hive in which the workers presented some appreciable difference. In order
to form a new breed, seclusion from other bees would, as we now know, be
indispensable; for since the introduction of the Ligurian bee into Germany
and England, it has been found that the drones wander at least two miles
from their own hives, and often cross with the queens of the common
bee.[495] The Ligurian bee, although perfectly fertile when crossed with
the common kind, is ranked by most naturalists as a distinct species,
whilst by others it is ranked as a natural variety: but this form need not
here be noticed, as there is no reason to believe that it is the product of
domestication. The Egyptian and some other bees are likewise ranked by Dr.
Gerstaecker,[496] but not by other highly competent judges, as geographical
races; and he grounds his conclusion in chief part on the fact that in
certain districts, as in the Crimea and Rhodes, the hive-bee varies so much
in colour, that the several geographical races can be closely connected by
intermediate forms.

I have alluded to a single instance of the separation and preservation of a
particular stock of bees. Mr. Lowe[497] procured some bees from a cottager
a few miles from Edinburgh, and perceived that they differed from the
common bee in the hairs on the head and thorax being lighter coloured and
more profuse in quantity. From the date of the introduction of the Ligurian
bee into Great Britain we may feel sure that these bees had not been
crossed with this form. Mr. Lowe propagated this variety, but unfortunately
did not separate the stock from his other bees, and after three generations
the new character was almost completely lost. Nevertheless, as he adds, "a
great number of the bees still retain traces, though faint, of the original
colony." This case shows us what could probably be effected by careful and
long-continued selection applied exclusively to the workers, for