In this same family of the _Sphingidæ_ cases are not wanting in which, on the other hand, the moths are far more closely allied than the larvæ. This is especially striking in the genus _Deilephila_, eight species of which are allied in the imaginal state in a remarkable degree, whilst the larvæ differ greatly from one another in colour, and to as great an extent in marking. These eight species are _D. Nicæa_, _Euphorbiæ_, _Dahlii_, _Galii_, _Livornica_, _Lineata_, _Zygophylli_, and _Hippophaës_. Of these, _Nicæa_, _Euphorbiæ_, _Dahlii_, _Zygophylli_, and _Hippophaës_ are so much alike in their whole structure, in the form of the wings, and in marking, that few entomologists can correctly identify them off-hand without comparison. The larvæ of these four species, however, are of very different appearances. Those of _Euphorbiæ_ and _Dahlii_ are most alike, both being distinguished by the possession of a double row of large ring-spots. _Zygophylli_ (see Fig. 50, Pl. VI.) possesses only faint indications of ring-spots on a white subdorsal line; and in _Hippophaës_ there is only an orange-red spot on the eleventh segment, the entire marking consisting of a subdorsal line on which, in some individuals, there are situated more or less developed ring-spots (see Figs. 59 and 60, Pl. VII.). If we only compare the larvæ and imagines of _D. Euphorbiæ_ and _Hippophaës_, we cannot but be struck with astonishment at the great difference of form-relationship in the two stages of development. In the case of _D. Euphorbiæ_ and _Nicæa_ this difference is almost greater. Whilst these larvæ show great differences in colour, marking, and in the roughness or smoothness of the skin (compare Fig. 51, Pl. VI. with Figs. 43 and 44, Pl. V.), the moths cannot be distinguished with certainty. As has already been stated, the imago of the rare _D. Nicæa_ is for this reason wanting in most collections; it cannot be detected whether a specimen is genuine, _i.e._ whether it may not perhaps be a somewhat large example of _D. Euphorbiæ_.