500 BRITISH LEPIDOPTERA. 



with its base resting on the yellow subdorsal line, is a velvety- 

 black patch darker and clearer than the ground colour, reaching 

 almost up to the central line. Behind these patches occur the 

 overflows of yellow dots from the lateral area. Fifth instar : 

 The dark larva moulted for the 4th time on the morning of June 

 23rd, the light one exactly 48 hours later. Directly after the moult, 

 the head is pale reddish, but it very soon becomes shiny black ; 

 however, a triangular section in the centre retains a reddish tinge. 

 Between the base of the triangle and the mouth is a transverse 

 yellow line with a yellow inverted cone at each end of it, but not 

 touching. The cones terminate each in a feeler at the side 

 of the mouth. The darker of the two larvae has entirely lost 

 all trace of a dorsal line, and both subdorsal and lateral lines 

 are narrowed. Its yellow markings have a decided tinge of orange 

 Subdorsal line even throughout and now quite free from orange 

 spots. The lateral line is broken beneath each spiracle and the 

 gap partly filled by a small reddish suffused patch. The spiracles are 

 situated in the yellow-dotted lateral area, just above the line. They 

 are upright elongated ovals, orange-coloured, and with a narrow 

 black slit. The yellow dots on the dorsum are confined as before 

 to the 5 or 6 narrow posterior subdivisions of the segment, and 

 do not reach the dorsal centre. The velvety-black patches are 

 somewhat reduced. The true legs shiny black, the first pair with a 

 small yellow spot at the base of the fleshy part ; the prolegs shiny 

 black, bases dull black. The caudal horn 8mm. in length, pale 

 yellowish-brown for half its length, darkening to blackish-brown 

 at the tip, and sprinkled with short black spines. There is a slight 

 backward bend in it at about one-third the distance up between 

 base and tip. It springs from a small mound of black ground 

 colour on the 8th abdominal segment. The hood-like fold of skin 

 behind the head, on the prothoracic segment, is prominent in these 

 recently moulted larvae. Ground colour deep black, in great contrast 

 with the yellow; rather lighter on ventral surface between the claspers. 

 The lighter larva differs from the one described above only in 

 the following particulars : — Yellow markings lighter, forming a 

 rich lemon colour ; the yellow dots in the enclosed lateral area 

 more numerous. The spiracles pale orange. The subdorsal and 

 lateral lines broader, the former swollen on each segment rather 

 before the centre, every swelling enclosing a small orange patch 

 (except on the thoracic segments) whilst the latter is interrupted 

 by dull red spots, each with a black dot near its lower edge. 

 The dorsal line is not quite obliterated. Its course is marked 

 by an elongated suffused yellow spot towards the end of each 

 abdominal segment except the last ; it is faintly indicated on 

 the thoracic segments. Ventral surface smoky-black, whitish down 

 the centre ; abdominal segments thickly sprinkled with minute 

 yellow dots. [Both these larvae died a few days after entering 

 the 5th instar, owing, no doubt, to the fact that the succulent 

 white-flowered Galium, on the flowers of which they were found 

 feeding on June 14th, 1903, and on which I continued to feed them, 

 became too relaxing after being kept a few days in water.] The 

 previous year, on June 14th, I found a larva at the beginning 

 of its 5th instar feeding upon vine. It exactly resembled the 



