British Bees / An Introduction into the Studies of the Natural History and Economy of the Bees Indigenous to the British Isles

by William Edward Shuckard

The primary division of the bees into two large branches, viz. into the Andrenidæ, or abnormal bees, and the Apidæ, or normal bees, is effected by the mode in which they fold the cibarial apparatus in repose. In the description of the structure of the imago, I have enlarged upon these organs, and for their explanation I must refer to that chapter where diagrams exhibit the structure of the different kinds of trophi of the bees, as well as their mode of folding. Here it is only necessary to notice that in the Andrenidæ, the joint at the base draws back the basal portion when protruded, and this basal portion is further jointed at the point of the insertion of the paraglossæ and labial palpi, and parallel with which joint the maxillæ are likewise jointed close to the sinus where the maxillary palpi are inserted laterally upon it. The basal portion thus throws the anterior part forward or retracts it, at the will of the insect, and in the latter case, being then in repose, it lies in contiguous parallelism to the basal half, but beneath it. When thus withdrawn, the short tongue itself, with its paraglossæ and labial palpi are sheltered beneath the coping of the labrum and the lateral protection of the mandibles, whilst the horny sheathing of the maxillæ protect the softer parts folding underneath.

In the Apidæ, or normal bees, the basal joint has the same action in withdrawing the entire organ into its place of rest; but the joint which gives it this power is not in an analogous situation to that in the Andrenidæ, for it is seated short of the joint which lies at the base of the several organs of the cibarial apparatus. By bending these downwards, it carries their apex backwards towards the basal fulcrum through the action of these two joints, and, when there, the more delicate ones are protected from abrasion or injury, by the lateral overlapping of the horny skin of the maxillæ. All being thus withdrawn within this covering, upon the joint which folds them back, seated at the base of the tongue, the labrum falls, and further to strengthen this protection, the mandibles close over it like forceps.

That this difference in the arrangement of the cibarial apparatus points to any distinctive peculiarities of economy has not been ascertained, for the habits of the Scopulipedes greatly resemble those of the Andrenidæ; although the habits of one of them, Anthophora furcata, are remarkably like those of the foreign genus Xylocopa, in its mode of drilling wood. But the Apidæ have cross affinities amongst themselves, thus Ceratina resembles Heriades, and some of the Osmiæ, in the way in which it nidificates.

The tongues of the Andrenidæ are always shorter, broader, and flatter than those of the Apidæ, in which they are always long, cylindrical, and tapering. In the first section of the Andrenidæ, the paraglossæ are obtusely terminated at the apex, thence called lacerated, and where they are fringed with brief bristles. The peculiar form of the tongue in this section suggests its being separated into two subsections, that organ being in the first subsection very broad and bilobated, which gives those insects their position in the series by approximating them to the preceding family of the Diploptera, or wasps, whose tongues have the same bilobate form, but each lobe in them is furnished with a gland. These tongues, in both cases of the wasps and these bees, may conduce to the building or plastering habits of the insects. The form may aid the wasp and the Colletes, the first in the moulding of its hexagonal papier-mâché cells, as it may the second in shaping and embroidering the silk-lined abode of its embryonic progeny. Why Prosopis should have this organization is difficult to conceive, unless it be from an analogy of structure incidentally previously referred to, beyond which any special object has hitherto escaped detection.

In the second section of the Andrenidæ, which have the paraglossæ entire and terminating in a point, the tongues all also terminate acutely with a lateral inclination inwards. In the lanceolate-tongued tribe they bulge outwards laterally, although pointed at the apex.

All this subfamily of Andrenidæ, excepting only the two genera reputed parasites, viz. Prosopis and Sphecodes, are essentially Scopulipedes, densely brush-legged, for the conveyance of pollen which they vigorously collect; but from the brevity of their tongues they are restricted to flowers with shallow petals and apparent nectaria, their favourite plants being the abounding Compositæ and Umbelliferæ, as well as the Rosaceæ, whence they derive the agreeable odours which many of them emit upon being captured.

Their peculiar mode of collecting is a further reason for bringing the brush-legged Apidæ collectively to the top of the normal bees, in juxtaposition to the Andrenidæ, where the transition is made very naturally from Dasypoda to Panurgus.

The whole of the cibarial apparatus, or trophi, is always complete in all its constituent parts throughout the Andrenidæ; and it is only with Ceratina, in the group of scopuliped Apidæ, that it begins to show the tendency it has to abnormal deficiencies, by the paraglossæ, in that genus, being obsolete. This characteristic, then, exhibits itself in the Nudipedes with two submarginal cells who are parasitical upon the Dasygasters, in whom also the maxillary palpi participate in a deficiency in the authentic number of their joints, whilst in Apis both maxillary palpi and paraglossæ are unapparent. This shows that the numerical completion of the organs of the mouth have nothing to do with the qualifications of the creature, the best endowed in other respects being thus curtailed, the final cause of which is not yet understood.

The shape of the tongue itself thus separates the Andrenidæ into three well-defined divisions readily perceptible. These, as I have just observed with respect to the differences in the mode of closing the oral apparatus in both cases, yield no clue to economy and habits, for which observation must supervene to illustrate it. This, patiently carried out, is very desirable, as it is still in discussion whether, notwithstanding the elucidation structure affords, Prosopis and Sphecodes are or are not parasitical. Structure says they are, for, like the cuckoo-bees forming the group Nudipedes in the Apidæ, they are destitute of the requisite apparatus for collecting pollen. Mr. Kirby, however, gives direct testimony in favour of Sphecodes being a burrower, in the case of which bee it ought not to be a matter of much difficulty to determine, for on sandy plateaus I have occasionally found it very abundant, especially where there was ragwort (Senecio) in flower in the vicinity, to which the males resorted; but being at the time more intent on other matters, I neglected the opportunity. Other observers concur with Mr. Kirby as regards Sphecodes, and also say as much for Prosopis (better known as Hylæus). I strongly incline to the opinion enunciated by Latreille and Le Pelletier de St. Fargeau, that they are parasites. My opinion is based upon peculiarities in them other than, although strengthened by, the negative characteristic of absence of polliniferous organs. A negative cannot be proved, it is true, yet what has been positively asserted may as certainly result either from defective observation, or from too strong a desire to find no parasites among the Andrenidæ. My reasons occur elsewhere in this work, and I need not repeat them. It is still an open question, and the young entomologist, if entering the arena unprepossessed, might win his spurs in determining it. It would be well worth the trouble of attending to for those who have leisure, and if decided in favour of the independency of these genera, which must be corroborated by a plurality of observations, and not confined to one locality, they would form strong and remarkable instances of a defective analogy in nature’s workmanship, and suggest looking further for the causes of so extraordinary an anomaly, and urge us to endeavour to trace the equivalent which supersedes it.

The main subdivision of the Apidæ results from the habits of the insects, which divides them into SOCIAL and SOLITARY. The only tangible characters the social tribes present to distinguish them from the solitary is the glabrous surface of the posterior tibiæ, with their lateral edges fringed with bristles slightly curved inwards, and which form, with the slightly indented surface of the limb, a sort of natural basket for the conveyance of pollen or other stores to the nest. This, however, has not been made use of as a main feature for scientific distribution, although they might follow the Dasygasters, as corbiculated bees, or little basket bearers, in which case they would form as pertinent a group as any of the rest, and the whole distribution of the bees, Apidæ, would then rest upon the absence of, or the mode in which the polliniferous organs were present. But the wonderful attribute of their extraordinary instinct prohibits their being treated with the rest in a consecutive line, and renders it rationally imperative that all the Cenobites should group together in a section by themselves, and separate from the rest. Therefore in my arrangement I have not availed myself of this very natural character, and here indicate it, to show that I have not passed it from not noticing it.