144 Mr. Poulton's notes in 1885 upon 



nearly meet at the apex of the head in S. lignstri, while 

 they do not come so near to complete fusion in A. atropos. 

 In both larvae the black bands attenuate considerably 

 towards the apex of the head. The most striking 

 resemblance, however, is afforded by the appearance 

 and position during the resting attitude of the thoracic 

 segments, which in both species are swollen and trans- 

 parent-looking, and without a trace of marking. All 

 the larval markings end abruptly at the anterior edge of 

 the first abdominal segment, except the border of the 

 anterior stripe, which just crosses the intersegmental 

 furrow in both species. The resting attitude of both is also 

 exactly similar, the head being retracted and the dorsal 

 surface of the swollen thoracic segments curved into a 

 quarter of a circle, as seen in profile. This is seen in the 

 Sphinx attitude of rest, and in other positions also. The 

 difference between the ground colour of the thoracic 

 segments and that of the others is very obvious in both 

 cases. The dilierence is perhaps best described by 

 saying that the former are yellower and paler, and 

 especially that the colour possesses a peculiar trans- 

 parency, which is absent from the rest of the body. 

 The thoracic segments are, however, less bright and 

 yellow than the ground colour in the region of the 

 oblique stripes. In a figure of the brown variety of 

 A. atropos, painted by Mrs. Owen Wilson, and sent to 

 me by Professor E. Meldola, the ground colour of the 

 thoracic segments is pink, while that of the others is 

 brown ; and the contrast is therefore much greater than 

 in the common variety. Mr. Stainton, in his ' Manual,' 

 describes the anterior segments of this variety as whitish, 

 and the rest of the body as brownish olive : I expect 

 that this is more correct than the impression con- 

 veyed by the figure, although the specimen which 

 Mrs. Wilson has painted may have been an unusual 

 variety. The black thoracic spiracle of A. atropos 

 resembles the ochreous anterior spiracle of S. ligustri, 

 and difi'ers from that of SnieyintJius ocellatus, &c., in 

 being unconcealed when the larva is at rest in the 

 Sphinx attitude. The relations of the oblique stripes 

 and borders to those of Sphinx ligustri are extremely 

 interesting. In Stainton's 'Manual' the larva of A. 

 atropos is described "with seven oblique lateral violet 

 stripes," and that of *S'. liguslri " with seven oblique 



