377 



Oiu' sotii situated over tlio stigma and s. suprasfif/jiKdis is qiiitc 

 likc a primary tuberciiluin and therefore agrees with .s-. dorso- 

 hiferalis on the thoracic scgments. S. infrastignialis lias become 

 doublé, but for the rest we hardly find under the stigmata any long 

 setae with a well-developed tuberculum. ïhere are many .s. bamlen. 



Instar IV. Length 13 mm. Duration 4 days. 



The number of secondary tubercula increases, the primary ones 

 e. g. on abd. segment 5 : .s-. dorsalis^ s. subdorsaUs^ s. sKprasfif/- 

 lual/s^ ,s'. dorsolateralis (arisen in instar III), s. infnisfi;/malis and 

 6'. poststigmalis remain distinct, the 6\ basales are indistinct. Under 

 s. subdorsaUs we find a new tuberculum which in form and size 

 agrees with the primary ones and which therefore perhaps agrees 

 with .s\ suhdorsalis in f. 



There is no real dorsal line, but exactly in the median plane 

 the tubercula and setae are wanting, so that there the skin has 

 a different aspect. 



Instar V. Length 16 — 25 mm. Duration 8 days. 



A dorsal line is faintly visible and coloured bright-yellow. In 

 front of the stigma we find one yellow spot, behind it are two 

 spots. There is no question of a stigmal line, but the pro- 

 longation of the spots is of a somewhat different colour to the 

 rest of the skin. 



The primary tubercula and setae are not distinctly visible, as 

 many secondary ones resemble them very much. The pattern is 

 lost and the animal makes the impression of possessing a coat 

 of irregularly homogeneously spread setae. The tubercula are now 

 coloured somewhat black. Under the stigma they are almost absent. 



Instar VI. Chrysalis. Smaller than P. brassicae (±20 mm.). 



I had at my disposal the variety which Buckler described 

 (Vol. I, p. 158) i. e. the bright, tender green one with many spots. 



The pupa quite agrees with that of P. brassicae, it shows dots 

 corresponding with the tubercula of the larva mentioned below 

 and the last segments are reduced in the same way : 



Macula dorsaUs, under it sometiraes a small spot which in my 

 opinion belongs to it. 



