50 



COLOUR-PATTERNS. 



[iNTROD. 





and 12,000 feet (from Scudder, Butterflies of X. America, i. pp. 477 — 480). Of this 

 insect, which is a very constant one, a certain striking aberration has been found, 

 always as a great rarity, in many lands. In this aberration the markings are 

 almost entirely rearranged. It is said to have been first described by Rambur under 

 the name var. Elymi, but this description I have never found. (The reference 

 quoted is Annates des Sci. d' observation, Paris, 1829, Vol. n. PI. v.) As often happens 

 with Variation, without coloured figures description is almost useless, but tbe 

 figures referred to are very accessible. In a British specimen of this aberration 

 the white bars are absent from the anterior costse and a series of white fusiform 

 blotches are present along the marginal border; two abnormal white spots are 

 also present near the anal angle, thus continuing the series down the wing [fig. 

 5, a.). The hind-wings are equally aberrant. The two large dark spots which are 

 usually on the disk between the median nervure and the inner margin are altogether 

 wanting. Between each of the nervures of the hind-wing is a white spot, whereas 

 in the normal form there is no white spot at all on the hind-wings. These white 

 spots on the hind-wings form a row parallel to the border of the wing and, as it 



Fig. 5. 



A. Clark's specimen of P. cardui, var. elymi from Ent. 1880. 



B. Newman's specimen. Brit. But., p. 64. 



C. P. cardui, normal, also from Newman. Brit. But., p. 64. 



