Part 7

In colour the humble bees vary remarkably, the variation occurring chiefly in the females. This variation is not so noticeable in this country, although in many species even here the variability is very great, but when we trace a common species such as terrestris, which varies very little here, over a large area such as the Palaearctic region its liveries are so diverse that its females have been treated as belonging to many different species. In the Siberian district its yellow bands become of a pale, almost whitish or straw colour, and the whole appearance of the insect is altered. If, instead of going north, we go to the Mediterranean region we find a large, fine form tolerably common, with bright yellow hairs on the legs. In Corsica {43} again we find a quite different form; entirely black except for the bright red hairs on the apex of the body, and bright red tibiae, clothed with red hairs. In the Canaries another coloration occurs: the whole insect is black with the exception of the apex of the body which is clothed with white hairs; but in all these the male varies comparatively little. In the Siberian and Canary forms it resembles the female, but in the others it varies very little from some varieties we find here. A rather similar series of varieties occurs in Bombus hortorum, another species little liable to variation here. In Italy and south-east Europe a form with entirely black body and black wings occurs, and in Corsica a black form with reddish hairs on the apical segments. The male keeps throughout very constant to its normal coloration. The tendency to vary towards an entirely black form seems to exist in nearly all the species, although in Britain black varieties of some are very rare.

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{44}

THE BEES WITH BIFID TONGUES

In this country we have only two genera in which the tongue is bifid at the apex, and on this account they are kept together as close allies in our classification. They are, however, very different in general appearance. One of these groups is called Colletes, on account of its habit of lining its cells with a gluey material, the other, Prosopis, on account of the markings on the face. The various kinds of Colletes are densely clothed on the head and thorax with brownish hairs, and the segments of the body have whitish bands composed of a dense, tight-fitting, duvet of hairs (pl. B, 10). There is in this country only one exception, a large insect like a hive bee, but rarely met with, its headquarters being the Wallasey Sandhills near Liverpool, and other localities in Lancashire. All the species tend to colonize; some building in huge colonies {45} in sandy cuttings, etc. They are preyed upon by a pretty little cuckoo bee called Epeolus (pl. B, 19), which is black, ornamented with brownish red and whitish spots. One of our best known species, Colletes fodiens, can often be found in abundance on the heads of ragwort along the sea-coast in July.

The other genus Prosopis is outwardly entirely unlike Colletes: its species are nearly all very small coal-black insects, with scarcely any noticeable hairs, rather unusually narrow and cylindrical in form; they emit a peculiar, agreeably scented fluid when handled; in the males the face is almost always white or yellow, in the females there is generally a yellow spot on each side near the eye. These little creatures are especially fond of burrowing in bramble stems. They like those which have been cut off in trimming the hedges, because in them the pith is exposed and they can burrow their way into it without gnawing through the wood. If any one, going along a hedge which has been trimmed, containing a lot of brambles, in the autumn or winter, would examine the cut-off ends they would soon find some with holes in them. These {46} may be the work of Prosopis, but there are other bees and fossors which also burrow in this way. So the stems should be brought home and opened. Then the Prosopis cells may be known by the fine membranous pellicle which surrounds them, but possibly even then a little jewel-bee cuckoo may be found in possession of the cell, instead of the rightful owner. When these little bees emerge they are generally to be found on wild mignonette, bramble flowers or those of the wild parsley tribe. Some are very common, others of great rarity. The males of this genus seem to have a peculiar tendency to develop eccentricities in the shape of the first joint of the antennae, or feelers, some having it expanded and concave, others rounded but thickened towards the apex; in only one British species, P. cornuta, does the female show any special peculiarity of form, but in this the face is produced on each side between the eyes into a distinct horn-shaped process. In the females there is scarcely any indication of pollen brush, and for this reason they used to be considered as possessors of cuckoo instincts, but there is now no doubt of their industrious habits; but {47} there is no other genus of industrious bees in this country, with the exception of Ceratina, with so little specialization for pollen collecting.

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{48}

THE BEES WITH POINTED TONGUES

All the genera, except the two mentioned in the last chapter, belong to this section, which comprises a variety of very different styles of bees, beginning with the short spear-shape-tongued species and ascending to the long-tongued species, which are considered to culminate in the hive bee. The habits of these genera vary very greatly in some respects; special notice has been or will be given of Halictus (pl. B, 12) and Sphecodes (B, 11), Andrena (B, 15, 16), Nomada (B, 18) and the other cuckoos, Osmia (D, 28) and Anthophora (D, 24, 25) and the leaf-cutting bees, but there are several other genera which deserve a passing notice, although their habits are not so peculiar as those of the specially selected ones. Cilissa, which is a very close ally of Andrena, is peculiar in having the hairs of the tongue erect and arranged almost in bottle-brush fashion. Its habits are much like those of {49} Andrena. Dasypoda, so called on account of the enormously long hairs of the pollen brushes of the legs in the female, is one of our most beautiful bees; it is of moderate size, a little more than half an inch long, with a brown haired thorax, and a black body with white apical bands on the segments; the hind legs are rather unusually long and the brush is composed of very long bright fulvous hairs, and when the bee returns home laden with pollen it is, as F. Smith says, "sufficiently singular to attract the attention of the most apathetic observer." It burrows in sandy places much after the fashion of Andrena, etc. The male is a different looking insect, entirely covered with yellowish hairs. Panurgus (pl. B, 17) is a curious genus of coal-black bees, whose females have bright yellow pollen brushes on their hind legs; they visit yellow composite flowers and the males often sleep curled up amongst their rays; they are most active bees, and burrow generally in hard pathways. I was watching a large colony of one of the species near Chobham in the end of June--they were burrowing in a gravel path, under which the soil was of a black sandy nature; the path was scattered all over with little black {50} hillocks of sand, and seemed alive with bees. It was showery weather, and occasionally the hillocks were washed nearly flat and a lot of sand must have entered their burrows--however, as soon as the sun came out again they cleaned out their holes and returned to their work. Panurgus is most businesslike in its pollen collecting; it flies in a rapid headlong way into a flower, and seems to do its best to bury itself, with a remarkable amount of action as if it was in a great hurry, and often bustles out of it again almost immediately and goes on to the next. Its methods suggest that it does more work in five minutes than any other bee would do in ten.

Another genus, Anthidium (pl. D, 27), this time one of the long-tongued bees, is peculiar in having the male larger than the female. Both sexes are black, variegated with yellow markings and spots, but the male is more ornate in this respect than the female and also has a peculiarly shaped body, which is unusually flat, curving downwards towards the apex, which is armed with five teeth, two bent ones on the sixth segment and three on the seventh. The female collects pollen on the underside of its body and collects the {51} down off the stems of various plants, especially those of the dead nettle or "labiate" tribe, with which it invests its cells. I cannot do better than quote the following from F. Smith: "This is the social bee which White in his History of Selbourne has so well described in the following words: 'There is a sort of wild bee frequenting the Garden Campion for the sake of its tomentum, which probably it turns to some purpose in the business of nidification. It is very pleasant to see with what address it strips off the pubes running from the top to the bottom of a branch and shaving it bare with the dexterity of a hoop shaver; when it has got a vast bundle, almost as large as itself, it flies away, holding it secure between its chin and fore legs.'"

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{52}

LEAF-CUTTING BEES

These are amongst the specially interesting of the bees in their habits. They are dull-brown coloured creatures rather like a stout hive bee in form (pl. C, 20). They all collect pollen on the underside of their body. They burrow either in decayed wood or in the ground, but they make their cells of pieces of leaves which they cut off from rose bushes or other plants; these cells when completed are wonderful works of art. Probably some of my readers may have noticed rose leaves with semicircular pieces cut out of them, and often with almost circular ones; this is the work of the leaf cutter (fig. 7).

20. Megachile maritima, female. 21. Coelioxys conoidea, male. 22. Coelioxys conoidea, female. 23. Nest of Megachile willughbiella.

{53} She alights on a leaf, holds on to the edge of the piece she wants to cut off with her legs, and then cuts it out by means of her jaws, or mandibles; as soon as it is cut free she uses her wings and so prevents herself from falling, and goes off with the cut off piece safely held under her body by her legs. I have frequently seen bees flying home with their leafy burden, and once or twice I have seen them cutting the pieces out. They cut round the piece they select with great rapidity--the marvel is that they can arrange so exactly as not to fall when the last attachment is removed. The pieces they cut have to be of several shapes in order to build up the cell they require; some are more or less lozenge shaped, some almost circular; the cells they make are somewhat thimble-shaped. The lozenge-shaped pieces are used to build up the sides and lower end of the cell, and the circular pieces to close it in with at the top; it is all cemented together with a gluey substance excreted by the bee. The burrows of the leaf-cutters are made, as stated above, either in the ground or in rotten wood. I have never had a subterranean nest to examine, but have had several nests in rotten wood under my notice, one of which is now before me (pl. C, 23). It is in a piece of very {54} soft willow, almost in a touchwood condition. So that by carefully cutting away the wood I have been able to expose the whole series of cells. Two distinct burrows run almost parallel to each other; both of them are slightly curved and each has contained six cells; these are about half an inch long, and they fit one over another in the tube as closely as possible so as to look like two long thick green worms. Each cell is composed of many pieces of leaf, and the final plug which closes the cell is often made of several rounds of leaf one over the other. The amount of labour taken by the mother bee to make these cells must be enormous. The cells are provisioned like those of any other solitary bee with pollen, etc., and the egg is laid upon it. Most of the leaf-cutters have their attendant cuckoos, which are rather smaller than themselves, of a deep black with white bands on the sides of the body. The female has a very pointed tail, and the male's body ends in a series of spine-like projections (pl. C, 21, 22).

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{55}

OSMIA AND ITS HABITS

I have tried as much as possible to avoid scientific names, but the misfortune is that there are hardly any popular names in use which can be attached for certain to any particular species, and unless this can be done it is of no use using vague names like the "Carpenter Bee", the "Mason Bee", etc. There are many carpenter bees and many mason bees, and though their habits may be alike in this one particular they differ among themselves in the way they use their tools, and it is necessary to know which one we are talking about. It is a common thing to hear people inveighing against Latin names, etc., but they forget that there are no English ones in use, and what is more important, that Greek and Latin names are common property to all nations, so that we can all know what we are talking about, whereas if we call an insect by an English name and the Russians {56} call it by a Russian name, the difficulty of coming to a mutual understanding is very great. This is only an aside to justify the use of classical names. I quite feel that for popular use in this country a good series of English names might be useful, but we have not got one, and it would require a great deal of care and thought to frame a nomenclature which would really be useable by the persons who require it.

I have made these remarks here because Osmia is a genus whose members vary very much in their habits, and some species of which, like sensible beings, adapt their habits to their surroundings, so that no name such as carpenter bee, etc., would apply to all the species, or, as a rule, even to one. Osmia rufa especially adopts several methods of nesting. This little bee is clothed more or less all over with yellowish hairs; it is compact in shape like all the other species of Osmia, and like them collects its pollen on the underside of the body. It may sometimes be seen flying up and down the walls of a house looking for a crevice to build in, but it is not the least particular as to where to form its cells. In one memorable case the female selected a flute {57} which had been left in a garden-arbour. The bee constructed fourteen cells in the tube of the instrument, commencing its first cell a quarter of an inch below the mouthhole. The flute is preserved in the Natural History Museum at South Kensington. At other times this species burrows in the ground, at others it makes its cells in crevices of old walls; it has been known to build in a lock, and is said sometimes to inhabit snail shells. Other species of Osmia almost always burrow in banks, but in no case does a habit seem to be uniformly adopted by a species. One well known and rare species, Osmia leucomelana, is a regular bramble-stick species, tunnelling down the pith in the centre of the stalks, but I once found it to my surprise in fair numbers nesting in a sandy bank. Other species again, as a rule, select snail shells to build in; they find an old disused shell lying about in some sheltered place and adapt it to their purposes, commencing their cells singly in the narrow whorls of the shell and side by side as they approach its mouth, i.e. if the shell be a wide-mouthed one like the common garden snail (Helix aspersa). F. Smith, who gives a very interesting account of these {58} creatures in his Catalogue of British Hymenoptera in the British Museum, mentions a case where the bee finding the larger whorls of the shell too wide constructed two cells across the whorl. Another very interesting case given by Smith is of a nest of many cells of the rare Osmia inermis (which in his days was known as Osmia parietina). A slab of stone, 10 inches by 6, was brought to him with 230 cocoons of this Osmia attached to its under side; when found in the month of November, 1849, about a third of them were empty; in March of the following year a few males made their appearance and shortly afterwards a few females, and they continued to come out at intervals till the end of June, at which time he had 35 cocoons still unopened; in 1851 some more emerged, and he opened one or two of the closed ones and found that they still contained living larvae; he closed them up again, and in April, 1852, examined them and found the larvae still alive; at the end of May they changed to pupae and appeared as perfect insects, the result being that some of the specimens were at least three years before reaching maturity. {59}

There is a nest of yet another style adopted by one of our species (Osmia xanthomelana). This is formed of a series of pitcher-shaped cells made of mud, constructed at the roots of grass. The species which makes it is rare and seems to have its headquarters on the coasts of Wales, although it has occurred in the Isle of Wight and elsewhere. This species also is not constant in its habits, as it has been known to make its cells underground. A very curious habit was noticed some years ago by Mr. Vincent R. Perkins in another species of this genus (Osmia bicolor; pl. D, 28); the species nests in the ground or in snail shells, but, in the case under his observation, Mr. Perkins found that the little bees covered up all the snail shells in which they had built their cells with short pieces of "bents" so as to make a little hillock over each about two or three inches in height, somewhat resembling a miniature nest of Formica rufa, the large horse ant, each mound containing hundreds of pieces. This is the only record I know of this habit, which must entail a large amount of labour for the bee.

These varying habits in the same species {60} show pretty clearly that these little creatures are not driven by any blind instinct in the adoption of their methods of nest building: they appear to have a distinct power of choice and adaptation according to their environment, unless of course it can be shown that the offspring of, say, a snail shell inhabitant follows its parents' habits, and that that of a ground borer does the same--but even that would not explain the case given by F. Smith, and quoted above, where an Osmia had filled up the whorls of a shell and then, finding the final whorl too large, placed two cells horizontally to fill it: that seems to indicate distinct design on the part of the bee and would be hard to explain as due to instinct. Unfortunately, with the exception of a very few, the species of Osmia are rare in this country, so that few opportunities are available for studying their habits, which are certainly amongst the most interesting of any genus.

24. Anthophora pilipes, male. 25. Anthophora pilipes, female. 26. Melecta armata, female. 27. Anthidium manicatum, female. 28. Osmia bicolor, female. 29. Bombus terrestris, female. 30. Bombus lapidarius. female. 31. Psithyrus rupestris, female.

{61}

A COLONY OF ANTHOPHORA

Anthophora pilipes (pl. D, 24, 25), one of our early spring bees, often forms enormous colonies. I have sometimes seen sandpits in which the sides were riddled all over with holes of this species, and where the insects were in such numbers that a distinct hum was audible from the vibration of their wings. In such colonies one is sure to detect some of their cuckoo associates, Melecta armata (pl. D, 26). They are deep black bees, much of the same size as their hosts but with more pointed tails and with a small spot of snow-white hairs on the side of each segment of the body; like other cuckoos they sail about in a more demure way than their hosts, but a more lively scene than a large colony of Anthophora can hardly be found. The Anthophora provisions its cells with honey and pollen, and its egg in consequence floats on the top--the {62} number of cells varies from five or six up to ten or eleven.