LITMIR.BIZ

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even than the thorax, sharp and powerful jaws, and with broad wings. The head and thighs are black, with a few spots of a yellowish white, and the abdomen is yellow, with a black spot in the middle of each segment. Its length rather exceeds half an inch. The actions of this insect do not belie its looks, for it is a fierce and active creature, seizing upon various bees and dragging them into its tunnel.

      Mr. F. Smith discovered the metropolis of this usually scarce insect at Sandown Bay, in the Isle of Wight, and has given an interesting description of its habits. He states that although it is so ferocious towards other insects, it appears to be perfectly harmless as far as man is concerned, allowing itself to be handled without even attempting to use its sting. Indeed, he was quite unable to provoke the insect to do so. Various bees were captured by the Philanthus, and the favourites seemed to belong to the genus Andrena, itself a burrowing bee, and the common hive-bee. The Philanthus seemed perfectly indifferent whether they attacked the comparatively small and feeble Andrena, or the formidable hive-bee, taking them as they came, and caring nothing for the sting. The Philanthus that burrowed on the top of the cliff, seemed to prefer the hive-bee, because the red clover attracted greater numbers of that insect. Those that made their burrows at the top of the cliff, took the Andrenæ. Of course, the Philanthus is obliged to catch more of the Andrenæ than the hive bees. Only one species of this genus is known in England; it is to be found in July and August.

      There is a very large genus of rather small humming-bees, many of which are popularly mistaken for wasps, on account of their sharply pointed and yellow banded abdomen; they belong to the genus Crabro, and are extremely variable in the material into which they burrow, and the insects with which they feed their young. Some species burrow into dry bramble sticks. If the reader should wish to obtain specimens of them, as well as other burrowers, he will find bramble, rose, and jessamine sticks most prolific in them. The best plan is to collect a quantity of these sticks and put them into glass tubes, with the ends stopped with wire gauze; there is then an absolute certainty of identifying the insect with its habitation. The spring is the best time for collecting. Sometimes these creatures are afflicted with parasites, which also are detained in the tube, so as to yield valuable information to the captor.

      Some species burrow in sand-banks and feed their young with gnats, others burrow into dead timber, and stock their tunnels with flies of various kinds. One very useful species, Crabro lævis, burrows in sand-banks, and provisions its nest with the noxious turnip-fleas (Halticæ), great numbers of which are needed to stock a single burrow. It is rather a social insect, many burrows being often found near each other. The turnip-flea has so hard a shell, that the young Crabro seems hardly capable of eating it. Mr. Smith, however, has remarked that another burrowing-bee stocks its nest with certain weevils that are almost too hard to be pierced with a pin, and that the shell is probably softened by the damp ground. The greater number of this group, however, are burrowers into the ground, and stock their nests with flies of some kind.

      Another species of this large genus, Crabro luteipalpis, is fond of making its burrows in the mortar of old walls, preferring those spots where nails have been drawn, making the process of burrowing easier for the insect. It is not uncommon in the outskirts of London. All gardeners, especially those who cultivate roses, ought to encourage this very little insect, and welcome its presence, for it provisions its nest with the aphides, or green blight, which infect the rose-trees, and which have destroyed so many promising plants.

      The female, which is the larger of the two sexes, measures only three lines in length. The colour is shining black, and the head is rather squared.

      Among other burrowing species of this genus we may mention Crabro varius, a rather long and slender insect, black in colour, with yellow spottings about the thorax. It prefers very hard fine sand, such as is found in partially excavated sand-banks, and provisions its burrows with gnats. It is tolerably plentiful.

      Our last example of the earth-burrowers belonging to this genus is Crabro Wesmoeli, which chooses similar localities, being mostly found in sand-banks. It carries off flies of different kinds for the food of its young. There is a very common insect, closely allied to the last mentioned genus, whose horns are worthy of notice. This is called Typoxylon figulus. It is a small creature, with a large head and slender abdomen. Its colour is black, and on the edges of the segments of the abdomen there is a little silvery shining down.

      It generally burrows into light earth, though it sometimes drives its tunnel into decayed wood. In either case, it provisions its nest with spiders, flying into the hedges, pulling the unfortunate spiders out of their webs, and carrying them into the burrow. One burrow contains a series of cells, which are separated from each other by partitions of sand, the particles of which are firmly cemented together by some glutinous substance secreted by the insect. Some species of this genus burrow into the pith of the bramble and other shrubs.

      One of the most determined of our British burrowers is the insect which is known by the name of Ammophila sabulosa. It has a large, squared head, wider than the thorax, a very long and slender body, and short though powerful wings. The colour is black, with a slight rust-red tint on the base of the abdomen.

      When the female has dug her burrow, she sets off in search of a caterpillar of proportionate size, and having conveyed it into her dwelling, she affixes an egg to the imprisoned larva, and goes off in search of another, carefully stopping up the entrance with stones. In fine weather she will fill one burrow with caterpillars in a few hours, and then begin another nursery for the future young. This species appears always to make use of caterpillars, but another allied species prefers spiders. Mr. F. Smith mentions that he has found in a high sand-bank as many as twenty females apparently hibernating together till suitable weather enabled them to pursue their usual economy.

      There really seems to be scarcely any genus of insect that is not seized upon by one or other of these burrowers, and packed away in a half living state to form food for their young. There is one of these solitary burrowing wasps called the Astata boops, deriving its specific name from its large round eyes, which in the male completely unite at the back of the head. The abdomen is shaped something like a boy’s peg-top, or a symmetrical turnip, the peg of the top, or the point of the turnip, corresponding to the top of the abdomen. Its length is about half an inch, and its colour is black, with a rust-red patch on the end of the abdomen.

      There is a remarkably pretty, and very variable, sand-wasp, which is plentiful in most parts of the country. The colour is black, and the abdomen is banded by four yellow bars. Its feet are also yellow. Mr. Smith has written a very interesting account of the proceedings of this insect.

      "Having frequently observed the habits of the type of this genus, Mellinus arvensis, and reared it from the larva state, a few observations are here recorded. When the parent insect has formed a burrow of the required length, and enlarged the extremity into a chamber of proper dimensions, she issues forth in search of the proper nutriment for her young; this consists of various dipterous insects: species of various genera are equally adapted to her purpose—Muscidæ, Syrphidæ, &c., are captured.

      "It is amusing to see four or five females lie in wait upon a patch of cow-dung until some luckless fly settles on it. When this happens, a cunning and gradual approach is made; a sudden attempt would not succeed. The fly is the insect of quickest flight, therefore a degree of intrigue is necessary. This is managed by running past the victim slowly, and apparently in an unconcerned manner, until the poor fly is caught unawares, and carried off by the Mellinus to its burrow. The first fly being deposited, an egg is laid. The necessary number of flies are soon secured, and her task is completed. Sometimes she is interrupted by rainy weather, and it is some days ere she can store up the quantity required.

      “A larva found feeding became full-fed in ten days. Six flies were devoured, the heads, harder parts of the throat, portions of the abdomen, and the legs, being left untouched. The larva spins a tough, thin, brown silken cocoon, passes the winter and spring in the larva state, changes to the nymph on the approach of summer, and appears about the beginning of autumn in the perfect state.”

      There is a genus of hymenopterous insects known by the name of Scolia, which are remarkable for their fossorial powers. The species represented in the engraving is called Scolia Xantiana,

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