THE EARLY STAGES OF COLIAS EDUSA. 175 



the six subsegments, owing to its breadth, the small black dots are 

 less orderly arranged than on the others. Around each l)lack dot is 

 to be seen a lighter ring. Under a lens of higher power, smaller 

 secondary black dots are discernible, from which smaller hairs issue. 

 Ventrally, the black dots are not surrounded by lighter rings, and the 

 hairs are much longer and stiffer. The hairs, when microscopically 

 examined, all appear unicellular. There are no dorsal lines, but on 

 some specimens the contractile vessel is discernible. Upon some of 

 those upon which it can be seen, on each side of it, on the prothorax 

 and mesothorax, are faint, rusty-brown lines. The spiracular line is 

 of a Avhite colour, merging into yellow as it proceeds ventrally. On 

 each segment, along the spiracular line, is a reddish spot, which is 

 found to be wedge-shaped. It is found on the 3rd and 4th sub- 

 segments most conspicuously, shading to yellow on the 5th. At this 

 point the spiracular line expands in width considerably. Immediately 

 below it, and about halfway along it, is a large black dot, which 

 reaches its maximum size upon the 7th and 8th segments, and is 

 almost obsolete on the prothorax and mesothorax, where the anterior 

 portion of the red blotch seems more orange than red. The portion 

 of the spiracular line upon the last abdominal segment is totally pale 

 yellow. The head, too, is covered with black dots, giving rise to 

 short bail's. These black dots are more sparsely scattered than on the 

 body. Upon the head is a faint depression in shape like an inverted Y. 

 Between the two arms of the Y the hairs are much closer together. 

 The head is slightly retractile into the second segment (prothorax). 

 The mouth-parts I did not describe fully. The maxillye are edged with 

 black, which passes imperceptibly through dark brown and yellow to 

 green. The antennte are slightly clubbed, and are tipped with black, 

 which extends closer to the base above. Attached to the antennae above 

 is a long hair, fully three times as long as the body-hairs, which is 

 periodically vibrated even when at rest. This hair is also much finer 

 than the body-hairs. Underneath is one very short stiff hair. The 

 eyes, six in number on each side, as usual, are arranged four in a 

 row ; three of these are close together ; the fourth is at about twice 

 the distance of the others ; the other two are outside these— the 

 first in a line with the iirst of the four, and the second intermediate 

 to the second and third ; the first three are dark brown in colour ; 

 the fourth is decidedly brown, but not so much so as the first ; the 

 last two are colourless. The legs and prolegs are green, but it was 

 found impossible to describe the latter owing to the larvcB clasping 

 the prolegs together. However, it could be seen that the hooks were 

 dark brown. Immediately below the spiracular line, and of the same 

 average breadth, is a sort of flange of the same colour as the back. 

 This is very sparingly covered with hairs. Its outline on the lower 

 side on each segment is that of the letter W, the part of the W sloping 

 to the head appearing to be more deeply impressed. Above the 

 spiracular line are small irregular wrinkles or puckers (not to be 

 confused with the transverse divisions or subsegments mentioned 

 above). The spiracles are dirty white in colour, and are surrounded 

 by a dark brown chitinous ring. In the centre is a black dash. The 

 first spiracles are not placed centrally in the spiracular line — their 

 lower extremity is slightly below it. The last pair of spiracles are 

 nearly central. The last pair but one are least central, and are 



