THE CRABROXIVM. 373 



form, its power of movement having been paralysed by the sting of the Wasp. Other larvae are brought 

 in \intil a sufficient supply has been accumulated, when an egg is deposited with them and the nest 

 closed up. Other species of the genus have similar habits, and those which form their nests in. dead 

 and rotten wood, bramble sticks, and similar situations, follow much the same mode of life, except 

 that they frequently divide their nests into several cells by earthen partitions. The larvae stored 

 in the nests generally belong all to the same species. 



The species of the genus Eumenes and its allies have the first segment of the abdomen very 

 slender towards its junction with the thorax, enlarged behind, and then again slightly constricted, 

 so that it has somewhat a pear shape, whence the only British species was named by Linnaeus 

 Vespa coarctata. This species, which is not uncommon on the continent of Europe, although 

 scarce in Britain, constructs small globular nests of mud about the size of a hazel-nut, and attaches 

 them either to the twigs of shrubs or to the surfaces of rocks and walls. These nests are stored by 

 the female with small green larvae, and it is supposed that two broods are produced in the year. 



A few species, forming the group Masarides, which chiefly inhabit warm countries, are 

 distinguished by having only two submarginal cells in the fore wings, which are also often only 

 partially capable of being folded. Two species (Celonites apiformis and Ceramius fonscolombi) occur 

 in Southern Europe. 



FAMILY CRABRONID^E. 



This family includes a considerable number of more or less wasp-like insects, often presenting 

 the same livery of yellow and black that is so common among the solitary Wasps, but occasionally 

 showing a red and black coloration, reminding us of the insects of the next family. The Crabronidse 

 (or Sphegidae as they are sometimes called) may, however, be distinguished from the members of 

 both these families by the circumstance that the prothorax is not produced at the sides so as to reach 

 the bases of the fore wings, but reduced to the ring-like structure that we have already stated to be 

 characteristic of the Hymenoptera generally ; and as a further difference from the true Wasps, it must 

 be noted that their wings are not capable of being folded longitudinally. These insects never form 

 societies, and all the individuals are therefore either true males or true females ; the antennae are 

 generally short, and not geniculated ; the eyes are generally oval, and the ocelli distinct ; there are 

 from one to three sub-marginal cells in the fore wings ; the tibiae and tarsi are spinous. 



In their habits, the Crabronidae present a considerable resemblance to the Solitary Wasps. The 

 females deposit their eggs in cells which are usually formed in the ground at the extremity of a passage 

 of some length, but sometimes in dead or decaying wood, or in the branches of brambles, and other 

 shrubs or trees, or built of earthy materials against walls, &c. ; and the food of the larvae consists 

 of various insects, which the mother generally paralyses by stinging them in the belly, so as to 

 pierce the nervous cord, and then packs into the cell in sufficient quantity to supply her offspring 

 with nourishment until it attains its full development. The egg is then deposited, and the nest 

 closed. The victims belong to various groups of insects, and include small larvae of Lepidoptera 

 and Beetles, and Grasshoppers, perfect Beetles, Flies, and even Bees, besides Spiders, &c. Some 

 species, instead of rendering their prey helpless by stinging them, kill them outright by a severe 

 bite. These latter do not store and close their cells, but leave them open, and bring in fresh 

 supplies of food until the larva is full-grown. Here also, as among the Bees, we find some 

 Cuckoo-like types, which make no nests, but deposit their eggs in the cells prepared by their more 

 industrious relatives. 



The typical genus Crabro is a veiy extensive one, including over 150 species, a great proportion 

 of which are inhabitants of Europe, while even. Britain, possesses more than thirty-five. They 

 are black and yellow insects of small and moderate size. They have only a single sub-marginal 

 cell in the fore wings, and the males in many species have the anterior tibiae and part of the tarsal 

 joints dilated into curious plates, which are sometimes apparently perforated like a sieve, a character 

 which has gained the largest of the British species the name of Crabro cribrarius. This species, and 

 many others, burrow in the ground, generally in hard sandbanks, and provision their nests with Gnats 

 and other Dipterous insects. One species (C. brevis), which frequents the same situations, has been 

 found to carry in small Beetles of the genus Haltica ; and another, which was observed making its 

 nests in the mortar of old walls, provisioned them with Aphides from the rose. Many species, 



