The Bees and the other stinging groups have four wings like all the Hymenoptera. These wings are almost always clear and transparent, at any rate amongst the British species, there being only one exception which I can call to mind in the female of the cuckoo of our large red-tailed humble-bee, which has the wings blackish; also they are never spotted, as in some flies. The hind or lower wings unite with the upper by a series of very beautiful hooks which extend along their upper margin and fix on to the posterior edge of the front wing, which is folded back on itself so as to receive them; in flight the two wings are united, but when at rest they separate; these hooks are beautiful objects under a microscope; their numbers vary; and in some cases this variation is useful in distinguishing closely allied species from one another. The hum of a bee is caused, to a great extent, by
the vibration of the wings, but it has been shown that a loud buzzing noise can be emitted by bees which have lost their wings; this proceeds from the spiracles or holes in the outer covering of the creature through which it breathes. It is therefore not always easy to say how much of the hum is caused by wing vibration and how much by the action of the spiracles. Some, in fact most, of our solitary bees are almost silent in flight, and their note can be heard only when large numbers are flying together; others have a very peculiar shrill hum, by which even the species can almost be recognized. In bright, hot, sunny weather their flight is more rapid and their note attains a higher pitch. The bees with the highest pitched hum with which I am acquainted are the two smaller species of Anthophora and Saropoda bimaculata.
In early spring, when it is hot in the sunshine and cold when a cloud covers the sun, it is no unusual thing to see a bee drop to the ground. The cold seems to paralyze altogether their powers of flight. When at rest a bee folds its wings along the sides of its back, but only in the wasp tribe is there the arrangement for them to be
folded longitudinally. The shape of the wings varies very little, but the arrangement and number of their cells vary considerably. There are some very interesting genera in which the neuration of some of the cells is so slightly indicated that they are hardly visible, and can be seen only when the wing is held in certain lights; these faintly indicated cells are nearly always those towards the apex of the wing, the neuration of the basal part of the wing being as strong as in the other genera. There are a few moths in this country which very much resemble, both in the colour of their bodies and their clear wings, the wasp tribe, but they may be known by the brown band of scales at the apex of the wings and also by the absence of the narrow waist, which exists in all the stinging tribes. The only wingless forms which we know are to be found amongst the ants and the fossors, and as a rule are females, but in a few cases in the ants, and in some foreign species of the genus Mutilla, the male is apterous also.
ON BREEDING ACULEATES, ETC.
Any one who wishes to study the life-histories of these insects, and has leisure to do so, can easily obtain various larvæ by digging for them in suitable places. If, for instance, during the summer, bees, etc., have been noticed entering holes in a certain bank or sandy spot, their larvæ or nymphs can be got in the autumn by digging down for about a foot in the direction of the holes, and if they be brought home and put into glass-top boxes they will generally emerge at their right time without giving any further trouble; it must, however, be remembered that the grubs are very soft and tender skinned, and it is better to avoid handling them if possible; they should be moved with a small soft camel-hair pencil, and it is well to put something soft at the bottom of the box so that if they fall in they will not be damaged. If the wood-boring
species are being collected, care must of course be taken in splitting the wood; most of these make a pupa case over themselves, and are in that respect easier to deal with. A label should be put in each box to show where the larvæ, etc., were found. An old rotten stump of a tree will often produce a good number of species. Then there are the bramble-stem borers; these can be left in the stems. I have generally found it convenient, after arriving home, to split the stems down, to see if there are any living creatures in them, and, if there are, to close them up again, and, tie a little very fine net or gauze bag over the top of each stem; in this way one can find out exactly what insects come from what stem, and determine the cuckoos (if any) which belong to each. As the season advances towards May, it is well to give all the larvæ, etc., an occasional glimpse of the sun; they should not be left in the sun long enough for them to get dried up too much, but the sun is a very important factor in tempting them to emerge; naked larvæ and nymphs, in glass-top boxes, should be treated very carefully in this respect, as they are deprived of their
natural surroundings, in which the actual sunshine would never reach them—it would be better to place them in a sunny room, screened off from the actual rays of the sun, so that its warmth only would be felt. If they do not emerge the first year, it should not be taken for granted that they are dead, as very likely they will appear in the following spring. I have bred leaf-cutting bees several times with great success, and others I know have been successful with many species. The fear is to get them dried up too much; it is therefore not desirable to keep them in a very hot room. When first the insects emerge, their hairs are often more or less matted together, and they should be put in the sun in a larger box, so that they can crawl about and clean themselves; portions also of the skin in which they have been enveloped frequently adhere to them for some little time, but as a rule, unless the creature be too weak, these are very soon cleaned off. Breeding is a fascinating amusement, but it requires a great deal of attention when the emerging season begins, as the boxes want constant watching, or the insects will emerge unnoticed, and, if not given proper