314 BRITISH LEPIDOPTERA. 



by the different degrees of depth attained by the lower part of the 

 purple border. When this becomes very dark some patches appear 

 on the other (inferior) side of the white stripe. [I described this 

 variety last year from a single instance found in the field, but it 

 was quite common among the larvae reared during the past summer.] 

 The larvae turned brown in many cases on August 21st, this stage 

 having lasted about nine days. Thus, the whole larval life lasts 

 about five weeks. There were many exceptions to the periods given 

 for each stage (which were, as far as possible, average instances) 

 (Poulton). Adult larva: Length from 3ms. — 3'5ins. (according to 

 position), the greatest width at 5th abdominal segment, just over '5 ins. 

 Body cylindrical, tapering gradually forwards from the 3rd abdominal 

 segment. The segmental incisions very clear and distinct, and there 

 are 8 poorly -marked abdominal subsegments. Head forming a 

 tall, curved-sided trapezoid, somewhat rounded at the crown and 

 slighted notched, '25ms. in height, and '19ms. in breadth ; the 

 suture of lobes distinct, the clypeal triangle small ; the surface 

 somewhat rugose (but as though it had been smoothed over after 

 being roughly granular), bright green in centre of face, but suffused 

 with white towards margins, a broad black band up the sides 

 of the face and over the crown ; the antennae stand out well, 

 but are not large in proportion to the size of the larva. 

 Thoracic segments, short and small, the skin much wrinkled, of a 

 clearer and more pellucid green than the rest of the body (probably 

 a tribal character) ; the scutellum on prothorax shows out distinctly 

 owing to its being yellower in colour than the rest of the body, 

 although it is far from distinct structurally. True legs small, black 

 at base, then a broad white band and lastly black again for the 

 terminal third. The abdomen smooth, bright, slightly yellowish, 

 green above, a paler duller green on sides, shading off to glaucous-green 

 ventrally ; the secondary hairs and primary setae can only be faintly 

 discerned under a powerful lens ; the spiracles large but not pro- 

 portionally so to size of larva, of a dull golden colour, without a 

 perceptible rim ; the caudal horn, hard, stiff, curved and spiny, 

 somewhat roughened, black in colour, except for a yellowish stripe 

 up either side for about half its length ; the oblique stripes slope 

 upwards and backwards, they form broad, dull, crimson slashes, 

 bordered by bright white ones of about equal size, tailing off below 

 into 4 white spots ; the last are well-marked shagreen-hairs with coloured 

 hases ; the double pigmentary character of these stripes is strongly ac- 

 centuated, the junction of the two colours being very sharp, and so vivid 

 are the colours that they give the impression of being painted on the 

 skin-surface instead of being beneath it ; the bright colours do not 

 extend beyond the segment on which each stripe originates, viz., 

 1 st to 7th abdominals, but they are continued forwards on to the 

 lower part of the next anterior segment by the white spots, and back- 

 wards above on the next following segment, by a clear shade of green, 

 deeper in tint than the ground-colour, bordered by brighter yellow 

 nearly as far as the centre of the dorsal area (Bacot. July 19th, 

 igoi). Newport's account of the musculature of the larva of Sphinx 

 ligustri, in his article " Insecta " (Todd's Cyclopedia of Anatomy 

 and Physiology, 1839, pp. 853—994), is among the best that 

 have yet been published. His diagram of the muscles and nerves 



