When full grown the caterpillar is green, roughened with yellow points, oblique stripes on the sides yellow, spiracles reddish, horn of the general colour, sometimes tipped with reddish. Head triangular in shape, but not pointed on the top. A reddish spotted form of the caterpillar is not very uncommon. In its very early life the head is rather triangular than rounded, as is the head of the young caterpillar of the previous species, and also that of the Eyed Hawk. Feeds on poplar, aspen, sallow, and willow, and may be found from July to September and sometimes October. Chrysalis blackish, rougher than that of the Lime Hawk. It lies in the ground so close to the surface that it is often exposed when the garden borders under or near poplars are raked over. The moth appears in May and June as a rule, but in backward seasons it may not emerge until July or even August. Caterpillars from eggs laid in early May are likely to feed up and attain the perfect state in late July, and eggs resulting from these will pass through the caterpillar state to that of chrysalis by about
September. Three broods have been obtained in one year, but this is exceptional and under a forcing method of treatment. The early stages are figured on Plate [4]. This is certainly the commonest of our Hawk-moths, and it seems to occur throughout our islands, except that in Scotland it is not recorded further north than Sutherland and Ross. Wherever there are poplars, sallows, or willows, there too most probably will be this caterpillar in its season; the moth also will be almost certainly seen by any one who may care to keep an eye on the stems of poplars or adjacent fences at the right time. Sometimes the insect will introduce itself to the household, after lighting-up time, much to the alarm of those who, not aware of the harmless character of their visitor, look upon it with considerable suspicion.
Distribution abroad—Europe (except the polar regions and Greece), Armenia and the Altai.
The Eyed Hawk-moth (Smerinthus ocellatus).
Except that there is sometimes an absence of rosy tinge on the fore wings, and that the brownish markings may be lighter or darker, this species does not depart very greatly from the typical form shown on Plate [7].
Cross pairings between the Eyed-hawk and the Poplar-hawk are not altogether difficult to obtain, but the female populi pairs more readily with male ocellatus than the female of the last named species will with the male of populi. Very few such cross pairings have been noted in a wild state, but several cases of the kind are known to have occurred in captivity. The results are hybrid moths, and these have some of the characters of each parent, and have received distinctive names. Thus the offspring of ocellatus ♂ × populi ♀ are the hybridus, Steph., whilst that of populi ♂ × ocellatus ♀ are referable to inversa, Tutt.
| Pl. 6. |
| Eyed Hawk-moth. |
| Eggs, natural size and enlarged; caterpillars and chrysalis. |
| Pl. 7. |
| Eyed Hawk-moth. |