The caterpillar (Plate [20], Fig. 3, figured from a coloured drawing by Mr. A. Sich) is green, with three darker green or reddish stripes along the back; the stripe along the area of the spiracles is dark green, edged below with white, but when the other stripes are reddish this is also marked with that colour. Several other forms have been described, and the caterpillar seems to be a most variable one. It feeds, from June to August, and again in September and October, on many kinds of low-growing herbage, such as restharrow (Ononis), clover (Trifolium), Matricaria inodora, etc.; also on furze or gorse (Ulex), and thorn apple (Datura). The blossoms and unripe
seeds are preferred in almost all cases, and flowers of the garden marigold will be found useful when these caterpillars are reared in confinement.
From eggs deposited by a female moth taken at Deal in the evening of June 17, 1904, the caterpillars hatched out in due course, fed up on wild convolvulus, pupated at the end of July, and the moths emerged during the last week of August and the first week of September. In another case, moths were developed in about forty-seven days from eggs laid in mid-July. In 1907 six caterpillars were found in South Devon during the second week in August, and one of these attained the moth state on September 3. Previous to 1906, which was a notable one for the species, the moth seems not to have been observed earlier than June, but in the year mentioned several were taken at the flowers of valerian during May, at Torquay. Caterpillars were plentiful on restharrow in the same district during June and July, and an example, presumably, of a second generation was captured at bramble blossom on August 11. In the same year and on the 15th of the month just noted, a specimen was reared from a caterpillar found on Ononis, July 18, and another specimen captured, August 24, as it flew in the sunshine on a slope of the South Downs. In Clarendon Wood, near Salisbury, Wilts, one example was taken at sugar, September 2, 1906. The species seems to be of fairly regular occurrence in Devonshire and Cornwall, but it has also been observed, more or less rarely, in many other English counties, chiefly those on the coast; in Pembrokeshire and Glamorganshire, South Wales; a few specimens have occurred in Co. Cork, and one in Co. Wicklow, Ireland. All that appears to be known of this species in Scotland is that one specimen has been recorded from Markton, Ayrshire.
Abroad, its distribution is extensive, ranging from Africa, the Canaries, and Madeira to Central and Southern Europe, and through Asia to India.
The Scarce Bordered Straw (Heliothis armigera).
This species (Plate [19], Figs. 6-8) has an almost universal distribution. It is found in Europe, Asia, Africa, America, and Australia. As regards the British Isles, it was first recorded by Mr. Edleston, who noted a specimen taken at Salford, Lancashire, by Mr. John Thomas, in September, 1840. This specimen, also one captured at Mickleham, Surrey, and others "taken in various localities," are referred to in the Entomologist's Annual for 1855. The following year one was reported from Exeter and one from the Isle of Wight. The summer of 1859 was a hot one (as were the two previous summers), and the species was recorded from the following localities: Brighton, Bristol, Cambridge, Edmonton, Isle of Wight, Ramsgate, Torquay, Weston-super-Mare, Worthing, and other places. Apart from the captures on the Devonshire coast, chiefly at Torquay, where the moth seems to occur pretty nearly every year, the records since 1859 are: 1866 (Scarborough); 1871 (Wakefield); 1876 (Hartlepool, and Kentish Coast); 1877 and 1881 (Gloucester); 1890 (Chatham); 1895 (Tunbridge Wells); 1901 (Isle of Wight); 1902 (Chester and Harwich); 1903 (Lewes). In all cases only single specimens. The species has been noted once in South Wales, and twice in North Wales; several specimens were secured in 1898 near Berwick-on-Tweed, and odd specimens have been recorded from Ireland.
The caterpillar is variable in colour; in one form it is green with a yellowish stripe along the sides, and in another the colour is purplish brown. The form figured (Plate [20], Fig. 2) is pinkish brown with a black-edged whitish line along the back, and a pinkish freckled and brownish edged yellowish stripe along the sides; the raised dots are white as a rule, but sometimes in the darker forms they are blackish. In some examples of the green form the dots and lines are black.
In 1869 two specimens of the moth were reared from caterpillars imported with tomatoes from Spain; twenty-three years later Mr. Arkle referred to the arrival here of H. armigera in the larval state with consignments of tomatoes, from Valencia, landed at Liverpool in the months of June and July. The late Mr. Tugwell reared larvæ, from eggs deposited by a captured female moth, on scarlet geranium; and there is a record of the finding of caterpillars on such plants, in the autumn of 1876, in the Isle of Wight. Specimens of the moth found at large in Britain occur in the autumn.