THE SOCIAL WASPS
Of these we have only seven different kinds, and with the exception of the hornet they are all very much alike. One often hears people say that they have seen such a large wasp that they think it must have been a hornet, but no one who has ever seen a hornet could mistake a wasp for one. A hornet is red-brown with yellow markings ([pl. B], 13), a wasp is black and yellow, and altogether a less formidable-looking creature ([pl. B], 14). Even a queen wasp is not so large as a small worker hornet. The hornet nests in hollow trees, our three commoner wasps nest, as a rule, in the ground, but occasionally in outhouses, under roofs, etc. One of the others as a rule makes its nest in shrubs, but occasionally in the ground, another always nests in a bush or shrub, preferring a gooseberry or currant bush, and the only remaining one is a cuckoo of one of the ground species. The gooseberry-bush
wasp is not a common species in the south, but in the midlands and north it is abundant. Wasps will eat most things, but are especially fond of syrups and sweets. One species, Vespa sylvestris, which seldom enters our houses, is very partial to the flowers of Scrophularia (Figwort). One rarely finds a plant of this in full blossom without finding its attendant wasps. I have seen other species of wasps also visiting it, but sylvestris is practically sure to be there. The diet which wasps provide for their larvæ is probably a mixed one, but consists largely of insects. Dr. Ormerod says that a microscopic examination of the contents of a larval stomach shows "the mass to consist of scales, hairs and other fragments of insects, hairs of vegetables and other substances less easy of recognition."
10. Colletes succinctus, female. 11. Sphecodes subquadratus, female. 12. Halictus leucozonius, female. 13. Vespa crabro, female. 14. Vespa vulgaris, female. 15. Andrena fulva, male. 16. Andrena fulva, female. 17. Panurgus banksianus, female. 18. Nomada ruficornis, var. signata, female. 19. Epeolus rufipes, female.
[face p. 36.
Wasps do not store honey in their nest; the papery nature of their cells would make such storage impossible. I dare say some of my readers will have noticed wasps sitting in the sun on a wooden paling busily engaged apparently eating something—they are really pulling off little fibres of wood which they chew up into a substance fitted for the walls of their cells; they will also chew paper, and the experiment has been tried of giving them coloured papers, which resulted in stripes of colour appearing in their nests. The different species vary somewhat in the architecture of their nests; but they are built very much on the same general plan. The population of some underground nests is very large. The Rev. G. A. Crawshay estimated the number in a large nest of Vespa vulgaris, which he took on September 20, 1904, at about 12,000; of these he actually counted, including eggs and larvæ, 11,370, and estimated the rest as having left the nest and escaped, so that anyhow the computation cannot be far wrong. This, however, was probably a very large nest. The cuckoo wasp (Vespa austriaca), formerly known as V. arborea, is an associate of Vespa rufa; its habits had been suspected for a long time, but Mr. Robson set all doubts at rest by finding the nymphs of the cuckoo in the actual nest of rufa. It is a rare species in the south, but far from uncommon as one goes north, and also in Ireland, where the relationship of the host and cuckoo have been
carefully studied by Prof. Carpenter and Mr. Pack Beresford. Vespa vulgaris has a beetle parasite, but this is somewhat of a rarity. This creature Metœcus paradoxus lays its egg in the cell of the wasp, and enters the body of the larva, eventually entirely devouring it. The hornet also has a beetle associate, but this is a great rarity. It is a large black species of the "Devil's coach horse" or "Cock tail" tribe (Velleius dilatatus), but in what relation it stands to the hornet beyond inhabiting its nest is not known.