366 BEITISH BUTTERFLIES. 



then, on one side or the other, the front dorsal row has only three 

 hairs, but there is a lenticle medially between the two rows. The pro- 

 thorax has sixteen hairs on each side, below the scutellum and includ- 

 ing the marginal set. The thoracic plate is a quadrant with the angle 

 behind, the arc in front; it has a hair at each external angle, and a 

 pair of len tides on the front margin, the left one of these is 

 accompanied by a second ; there is also a lenticle near each hair. The 

 anal plate (in this specimen) carries a single median hair in front and 

 a median lenticle behind it ; the other hairs, fourteen altogether, 

 belong to the 9th and 10th abdominals and are all more or less 

 marginal. The spiracles, rather larger than the hair-bases or Jen- 

 ticles, are black raised cylinders with a most remarkable structure of 

 the summit, rather difficult to quite determine ; the margin seems to 

 be raised into eight or nine (lighter-tinted) points and there are 

 corresponding hollows, interior to' these, one between each two points: 

 the centre is not open but in what precise way it is closed cannot be 

 seen. The lenticles are little circles of dark chit-in, the inner margin 

 raised but both inner and outer quite smooth, the centre closed by a 

 membrane with four or five dark spots ; this smoothness of the 

 lenticular rings is noteworthy, as, in the larva of A. coridon, in which 

 the spiracles are a little less elaborate, the lenticles closely imitate the 

 spiracle in having raised points or knobs along their edges. Below 

 the flange is a lenticle at the front margin of the segment on the 1st 

 and 2nd abdominals, and at the posterior margin on the 5th, 6th, and 

 7th abdominals ; there are four hairs above the legs in a group on the 

 thoracic segments ; there are similarly four, sometimes five, on the 

 abdominal segments that seem to belong to tubercle vi. At this level 

 there is, deep in the incision in front of each of the abdominal 

 segments 1 to 7, a curious, nearly black, mark of undetermined nature. 

 There are four minute hairs (vii ?) at base of prolegs. Each proleg 

 has four hooks two to each pad and the anal claspers seem to be the 

 same. The skin-points are very fine and transparent. A specimen 

 preserved on a slide has changed colour, but has brought out in great 

 detail the difference between the darker and lighter hues, the darker 

 being now bright pink ; it shows continuous yellow on the flange, dorsal 

 and lateral, also two less conspicuous, i.e., less straight, broad or con- 

 tinuous, series, between these, with further branches more or less breaking 

 up the dark colour ; the pink, except quite on the dorsum, is arranged 

 in very beautiful minute reticulations, apparently corresponding with 

 the skin points ; this maybe due to the skin-points acting as lenses, 

 but more probably in an actual distribution of pigment corresponding 

 with the dermal cells. Third instar (November 18th, 1908): Length 

 2-6mm. ; body very thick and short ; colour greenish-olive, with 

 yellow dorsal ridges the colour tending to stretch across the dorsal flat 

 and does soon mesothorax where the dorsal"flat" is widest and the ridges 

 appear to turn round the front border of the segment and meet ; it is 

 thickest at metathorax ; the " slope" is a little broader than the dorsal 

 flat on the mesothorax, about two and a half times on the 6th 

 abdominal segment ; the flat narrowing thus backwards, whilst the 

 slope decreases comparatively little. The yellow of the lateral ridge 

 is narrow. The black spiracles are conspicuous black spots. The 

 bair-bascs, etc., though more numerous than in the previous skin, are 

 individually smaller. The spiracles arc raised cylinders as high as 



