218 BRITISH LEPIDOPTERA. 



a trapezoid, and separated from one another by two subsegments 

 (being placed on subsegments 2 and 5) • on the meso- and metathorax 

 iii is a twin-haired oval tubercle, and there is a single-haired subspira- 

 cular (? v) on the anterior margin of segment. The 1st abdominal differs 

 from all other segments in that iv and v sometimes form a twin-haired, 

 oval tubercle *, directly beneath the spiracle, whilst the spiracle and iii 

 (directly above spiracle) appear to be further forward than on the 

 other segments, and are apparently situated on the 3rd subsegment. On 

 the other abdominals iii is directly above the spiracle apparently on sub- 

 segment 4 • iv is directly beneath the spiracle, and larger than v which 

 is quite close to the anterior margin, apparently on the 1st subsegment, 

 and slightly above the level of iv, but they are both clearly situated 

 on the lateral flange which is, however, only slightly marked. Hairs 

 very short and stumpy, but apparently blunt-ended and neither 

 knobbed nor forked. The 8th abdominal spiracle is much the 

 largest, the 7th abdominal comes next and that on theprothorax next, 

 whilst those on abdominal segments 1 — 6 are not more than half the 

 size of that on prothorax so that the disparity in size between those 

 on the 7th and 8th and the other abdominal segments is very great. 

 There is a pale narrow mediodorsal line. [Bacot. Described from 

 larva received from Chapman, preserved in formalin.] Second instar 

 (still wanted). Third instar: Plump, full-bodied, but not squat; 

 tapering gradually from 3rd abdominal segment to last thoracic, and 

 thence more rapidly to head. The head is small for a well-grown 

 larva of this size, rounded and but slightly taller than wide. The 

 horn is short, upright and pointed, carries two bristles at sum- 

 mit, and has a thorny appearance, due to numerous smaller 

 bristles, and their conical bases scattered upon it, the skin of horn 

 is shiny and chitinous-looking, black for upper 'two-thirds, yellow or 

 orange at base. The true legs are black. There are 8 subsegments to 

 each segment, the first three of which form one large division which ap- 

 pears to present both a structural and a colour character. The larval 

 colours are very brilliant and sharply contrasted, consisting of vivid 

 green-yellow with intense velvety black and white spots. The head 

 is black and orange, the crown and face black, with a varying area 

 of orange, which may be only a narrow streak or a broad band 

 or belt, running horizontally round the sides of the head and across the 

 face, just above the mouth. The body colours also vary in the 

 proportion of green-yellow and black, in some larvae the black 

 area being much increased. There is a broad bright yellow 

 mediodorsal band from head to base of horn, it commences again 

 behind the horn and is continued to the anus ; the ground-colour of the 



* Reference to larvae of Theretra porcellus and Sphinx ligustri in 1st stadium 

 shows that in these iv and v are well separated on the 1st abdominal, both are on the 

 lateral flange at or near the same level. Larvae of Celerio gcUUi and its allies in this 

 stadium are unfortunately not at hand for reference so that I cannot say whether this 

 marked aberrational character oi united iv and v in Hyles euphorbiae is ever found in 

 them (Racot). Chapman notes that the larva of //. euphorbiae examined by Bacot must 

 have been aberrant, that he has examined two larvae, in both of which the arrangement 

 of iv and v on the 1st abdominal is such that, although brought nearer together, iv and 

 v still remain quite distinct and at some distance from each other. A subsequent ex- 

 amination of 8 examples in Bacot and Chapman's possession results in showing- that 

 tubercles iv and v on ist abdominal are : (1) Left conjoined, right normal. (2) Left 

 conjoined, right approximated. (3) Left normal, right conjoined. (4) Left conjoined, 

 right conjoined. (5-8) Normal on both sides (vide, Eut. Rec., xv., April no.). 



