The Privet Hawk (Sphinx ligustri).
A specimen of the female sex is figured on Plate [12]. The white clouding or mottling on the pale brown colour of the fore wings varies in intensity and is sometimes tinged with pink, especially at the base of the wings; often it is only noticeable at the tips of the wings and on the outer area; the blackish suffusion from the inner margin through the central area and the black streaks between the veins are rather more constant. On the hind wings the pinkish tinge between the black bands may be faint or entirely absent; the central black band varies in width, and is sometimes so much expanded that it absorbs the basal half of the first band.
When full grown the caterpillar measures about three inches in length and has a very substantial appearance. It is of a pretty green colour, with seven oblique white stripes, each of which has a purplish front edging; the spiracles are yellowish. The head is rather more grass green and marked with black in front. The curved horn is blackish on the upper side and yellowish below. The colour of the caterpillar in its younger stage is yellowish, due to the presence of yellow dots, it also has some tiny hairs; the horn, which is bristly and slightly forked at the tip, is a conspicuous feature at this age on account of its length and dark colour as compared with that of the creature itself. Just before changing into the chrysalis, a brownish tinge is assumed, and very rarely caterpillars of a pinkish or purplish tint have been found.
It feeds on privet (Ligustrum vulgare) in July and August; often to be seen resting on the upper part of the longer sprays of the food plant. Sometimes a dozen or more may be found on one short strip of privet hedge. They are much subject to the attack of ichneumons. Other food plants are lilac, ash, lauristinus, and some other shrubs. Mr. Step informs me that on
August 18, 1907, he found three larvæ feeding on teasel at Ashtead.
The caterpillar will burrow some depth underground before constructing its pupal chamber. The chrysalis, which is reddish, or blackish-brown in colour, is figured with the other stages on Plate [13].
The moth usually emerges the following June or July, but there are at least two records of its remaining in the chrysalis during two winters.
The southern portion of England appears to be the principal British home of this moth. It is more or less scarce in the midlands and northwards. In Scotland it has only been recorded from southern counties, and in his "Catalogue of the Lepidoptera of Ireland," Kane states that he has no certain record of its occurrence in that country. Widely distributed through central and southern Europe, extending northwards to south Sweden and Finland, and eastwards to Amurland, China, and Japan.