190 NOTES ON THE SEASONS OF 1893,
With regard to insects, we are only in a position to discuss a
very few species, because the habits of so few forms have been
studied with sufficient care from year to year to enable us to
institute a comparison. Bees stand out as an exception, and the
season has left its impress upon that exception. It may be summed
up by saying that no "swarming" occurred. The wherefore of this is
not known. We can only say that for some reason the queens were
not prolific, and as food is known to affect the entire organism of
the queen, it is probable that a scarcity of certain food brought
about that untoward result. We have here a case in which local
extinction might have occurred had it not been for artificial care,
and some experienced bee-keepers are even now fearing the results
of wintering their stocks, which are known to be weak.
Wasps, on the other hand, multiplied to such an extent as to
have been aptly described as a plague. The reason undoubtedly
was due to the fair weather in the spring allowing almost every
mother-wasp to rear a progeny. These stand on a very different
footing to bees, for every mother or queen-wasp is the equivalent, in
the spring, of a whole hive or stock of bees, and has to perform in
her own person the functions of that entire colony. The mother-
wasp may have been more or even less prolific than ordinary, but no
observations have, so far as we know, been made.
Hot and prolonged summers are generally looked upon as being
the nursing mothers of vast swarms of aphides and other insects of
an Egyptian plague character; but it is perhaps worth remarking
that nothing much above the normal appears to have been noticed
except in the case of wasps, and even they were local.
The extreme dry weather most certainly affected a part of the
molluscan fauna in a peculiar manner. In the case of land-shells
the period of enforced rest was much prolonged, there being no
dews at night. Whether this had a deleterious effect we do not
know. Some fresh-water molluscs must have suffered a serious
diminution in numbers where the ditches and ponds dried up. I
watched with particular care a very small colony of Limneids
(Lymnaea palustris var. torvus), which had during the past few
years dwindled down to probably less than a dozen individuals.
Three of these, which was all I could find, I carried to deeper water,
or otherwise I feel quite sure the colony must have perished. I may
mention that I saw one of these in the act of pairing with an
individual of the normal type of L. palustris. This I think is a