_The Lime Hawk_ (_Smerinthus Tiliae_)
This beautiful moth (fig. 5, Plate IX) is easily identified by its rich olive green and brown wings, the fore pair of which have very conspicuous patches of deep olive, sometimes uniting to form a continuous central bar. It flies in May and June.
The caterpillar is rough, of a pale green colour, dotted with yellow, with seven oblique yellow stripes on each side. Thus it is very like the larva of _Populi_, but may be distinguished from that species by the orange spiracles, and by the horn, which is rough, blue above, and yellow beneath. Behind the horn, too, there is a flat purple or violet scale with an edging of orange.
The food plants of this species are the lime (_Tilia vulgaris_), elm (_Ulmus campestris_), and the hazel (_Corylus Avellana_), from which the larvae may be beaten in August and September, and from under these the pupae may be dug out during the winter months.
_The Humming-Bird Hawk_ (_Macroglossa Stellatarum_)
The genus to which this insect belongs contains three interesting British species. Their antennae are thickened toward the end, but terminate in a small curved bristle. Their wings are rather short and broad; their bodies are very thick, terminating in a broad tuft of hair; and the perfect insects fly during the daytime, delighting in the hottest sunshine. The larvae feed princ.i.p.ally on low-growing plants, and undergo their metamorphoses on the ground among the foliage.
On Plate IX (fig. 6) one of these pretty moths is shown. It is the Humming-bird Hawk, so called on account of its exceedingly rapid humming-bird-like flight, accompanied by a soft humming sound.
This insect is very common; and, being very partial to the attractions offered by many of our favourite garden flowers, it ought to be well known to all observers of nature.
Take your stand near a bed of petunias or verbenas, or close to a honeysuckle in bloom, on any hot summer"s day, and you are almost sure to be rewarded by a peep at the wonderful flight and interesting ways of this moth. It makes its appearance so suddenly that you first view it as an apparently motionless insect, suspended in the air, and thrusting its long proboscis into the tube of an attractive flower. Its wings vibrate so rapidly that they are quite invisible, and give rise to the soft hum already mentioned. Then it darts from one flower to another, making a similar brief stay before each while it sucks the grateful sweets. Raise your hand as if to strike, and suddenly it vanishes you know not where.
But it is as bold as it is wary, and will often return to the selfsame flower as if to defy your power. A sharp sweep of your net in a horizontal direction, or a sudden downward stroke, _may_ secure it; but if you miss it, as you probably will, it will disappear like a phantom, and give you no opportunity of making a second attempt.
This moth is on the wing throughout the hottest months of the year--May to September, and will often greet you as you roam over flowery banks in search of b.u.t.terflies.
The caterpillar feeds on the lady"s bedstraw (_Galium verum_), hedge bedstraw (_G. Mollugo_), and the goose gra.s.s (_G. Aparine_), and may be searched for in August and September. It is rough, green or brownish, and dotted with white. Along each side are two light lines. The horn is thin and short, rough, and points upwards.
_The Broad-bordered Bee Hawk_ (_Macroglossa Fuciformis_)
The two other moths of this genus are called Bee Hawks from their resemblance to the humble bee. They are very much alike, but may be distinguished by a difference in the width of the dark border of the wings; and are named Broad-bordered and Narrow-bordered respectively.
The former is ill.u.s.trated in the woodcut appended. The fore wings are transparent like those of bees, with a dark central spot and a broad reddish-brown hind margin. The base and costa are black and tinged with green. The hind wings are similarly coloured, but have no central spot.
The body is olive-brown, with a broad reddish belt, and behind are tufts of hair, which are spread out when the insect flies, just after the manner of the tail feathers of a bird. The moth flies in May.
[Ill.u.s.tration: FIG. 102.--THE BROAD-BORDERED BEE HAWK.]
The larva resembles that of _Stellatarum_, but exhibits a violet tint above the legs. Its horn, too, is curved, and of a reddish or brownish colour. It feeds on the honeysuckle (_Lonicera Periclymenum_), ragged robin (_Lychnis Flos-cuculi_), evening campion (_L. vespertina_), red campion (_L. diurna_), lady"s bedstraw (_Galium verum_), and the field scabious (_Scabiosa arvensis_), during the month of July.
Family SESIIDae--THE CLEARWINGS
This family contains fourteen very pretty British insects that differ very much from other moths in many important and interesting particulars.
Their antennae, like those of the _Sphingidae_, are thickest beyond the middle, and those of the males are slightly _ciliated_ or hairy. Their bodies are slender, and terminate behind in tufts of hair. The hind wings in all cases are transparent, margined and veined with black or brown; and the fore wings also, in most cases, have transparent bases.
These moths delight in the hottest sunshine, and may be seen gracefully hovering over the flowers in our gardens, looking more like gnats, bees, and wasps, than moths.
The larvae of these insects are all wood-eaters, and spend their time within the stems of shrubs and trees, eating out galleries in the material that forms both their food and their home. Within these they also undergo their changes, and do not expose themselves to the free air and light till they reach their perfect stage.
_The Hornet Clearwing of the Poplar_ (_Trochilium Apiformis_)
We can find s.p.a.ce for a mention of only two of the clearwings, the first of which is an insect that closely resembles the dreaded hornet, and whose larva feeds in the stems of poplars--features which will account for the above name.
[Ill.u.s.tration: FIG. 103.--THE HORNET CLEARWING OF THE POPLAR.]
The head of this species is yellow, its thorax brown with a large yellow patch on each side, its abdomen yellow with two brown belts, and its legs reddish orange. The front wings are transparent, with brown costae, and all the wings are margined with brown.
The caterpillar, when full fed, makes a coc.o.o.n with silk and the chips of wood that it has bitten off; and in this undergoes its metamorphoses.
It is fully grown in April, and the moth flies from the end of May to the end of July.
There is another "Hornet Clearwing," the larva of which feeds on the stems of osiers. It may be distinguished from the species just described by a yellow "collar" between the head and thorax, both of which are blackish.
_The Currant Clearwing_ (_Sesia Tipuliformis_)
This is by far the commonest of all the Clearwings, and only too well known to those who grow currants. Examine the shoots of _Ribes rubrum_ (red currant) and _R. nigrum_ (black currant), especially those that present a withered or half-withered appearance, and you will almost certainly meet with signs of the presence of this intruder. Little wriggling larvae occupy the pithless stems throughout the winter and spring. These are full grown in April, and in June the pretty little moth emerges through a hole in the side of a shoot, leaving the empty pupa case within its former home.
[Ill.u.s.tration: FIG. 104.--THE CURRANT CLEARWING.]
The fore wings of this moth have black margins, and a black transverse bar beyond the middle. The body is black, with three pale yellow belts, and black tufts of hair at the tip.
Family--ZYGaeNIDae
The remaining family of the _Sphinges_--the _Zygaenidae_--includes seven British species, three of which are known popularly as the Foresters and the others as the Burnets.
Their antennae are thickest beyond the middle, but do not terminate in a hook. Their wings are narrow and completely covered with scales.
These moths are very sluggish creatures, spending the greater part of their time at rest on the stems of low-growing plants. When they do fly, their flight is short and heavy, and their pretty wings glisten in the sunshine (for they are lovers of the sun), giving them the appearance of bees rather than of moths. On account of this natural sluggishness, they are exceedingly local, for they never move far from the spots where their food plants abound, and where they had previously spent the earlier stages of their existence. Thus we often come across a very limited piece of ground actually alive with them, and outside which not a single specimen is to be seen.
The larvae, too, are sluggish creatures, with soft and plump cylindrical bodies and no horns. I will briefly describe three members of this family.
_The Forester_ (_Ino Statices_)
The fore wings of this species are semi-transparent, and of a beautiful glossy green. The hind wings also are semi-transparent, but of a dull smoky tint. The thorax and abdomen are both of a brilliant metallic green colour. The tips of the antennae are blunt, and the male may be distinguished from his mate by these organs being slightly fringed or ciliated.
[Ill.u.s.tration: FIG. 105.--THE FORESTER.]
The caterpillar is dingy grey or greenish, with a row of black spots down the back, and a whitish stripe on each side. It feeds on the common sorrel (_Rumex acetosa_) and the sheep sorrel (_R. acetosella_), and when fully grown it spins a coc.o.o.n on the stem of its food plant, and there changes to a chrysalis.
The larva may be found during May and early June. The chrysalis state lasts only a few days, and the moth is on the wing during June and July.
_The Broad-bordered Five-spotted Burnet_ (_Zygaena Trifolii_)
On Plate IX (fig. 7) will be found a coloured representation of this Burnet. The two crimson spots in the base of the fore wing are very close together, and often touch. The same remark also applies to the two spots on the middle of the wing. A glance at the list of British Moths (Appendix I) will show that we have also a _Narrow_-bordered Five-spotted Burnet. This insect is very similar to the species now under consideration, but may be identified by the narrower purplish margin on the hind wings, and also by the shape of the antennae, which are not thickened so much near the end as they are in _Trifolii_.
The larva of the present species is yellowish or greenish, with a row of black spots on the back and a row on each side. It feeds on the bird"s-foot trefoil (_Lotus corniculatus_), hop trefoil (_Trifolium proc.u.mbens_), and the horse-shoe vetch (_Hippocrepis comosa_) in May.
Late in May or in early June the chrysalis may be found in a silken coc.o.o.n attached to a stem or leaf; and the perfect insect flies during June and July.