PIERIS BRASSIC^. 47 



the lateral stripes the black marks are fewer and reduced 

 to dots. On each clasper is a slightly larger black dot, 

 and the head is a good deal marked with the same 

 colour. 



The ground-colour of the pupa (Fig. 25) is a greenish- 

 white, sometimes slightly tinged with bluish-green or red, 

 and always profusely sprinkled with small black dots. 

 It has a medio-dorsal serrated keel and two lateral ones, 

 the projections bearing large black marks and being tipped 

 with yellow. The anterior extremity is pointed ; there is a 

 high medio-dorsal point on the thorax, as well as a large 

 projection on each lateral keel near the tip of the wing- 

 cases. 



The outline of the imago (Fig. 22) is simple, the wings 

 are rounded, the costal margin of the fore-wings is dis- 

 tinctly arched and the tip pointed. The ground-colour is 

 creamy-white. On the upper surface the fore-wings are 

 tipped with a broad black mark, gradually narrowing till it 

 disappears on both the costal and hind margins. On the 

 hind-wings is a small black spot about the middle of the 

 costal margin. The base of all the wings is usually 

 sprinkled with black scales. The female (Fig. 24) has, 

 in addition, a circular spot near the centre of the fore- 

 wings and another between it and the inner margin, along 

 which is a club-shaped black mark, starting near the 

 second spot and gradually narrowing towards the base of 

 the wing. On the under-surface (Fig. 23) the ground-colour 

 of the fore-wings is creamy, the tip being yellow instead of 

 black, while the two circular spots of the upper surface 

 of the female are present in both sexes. The hind-wings 

 are yellow, powdered with black scales, and having just a 

 trace of the black spot found on the upper surface. 



Specimens sometimes occur much more thickly sprinkled 

 than usual with black scales, which give them a very dusky 



