THE INHERITANCE OF WING-COLOUR IN 

 LEPIDOPTERA. 



V. MELANISM IN ABRAXAS GROSSULARIATA 

 (VAR. VARLEYATA, PORRITT). 



By H. ONSLOW. 



(With six Text-figures and Plate XIX.) 



Several examples of melanism have already been investigated, and 

 their inheritance described in previous papers. The chief interest of 

 these melanic strains lay in the fact that they were all discovered in 

 the south of England, and far from any manufacturing centres. As 

 appears to be usual, the melanic variety in each case behaved as a 

 simple mendelian dominant. 



That exceedingly variable species, Abraxas grossulai'iata, possesses 

 a black variety, known as var. varleyata, Porritt', found in Hudders- 

 field, and now established as a domesticated strain. Basing his opinion 

 on a single family, bred by Mr L. W. Newman (see the third table), 

 Mr Bateson'^ concluded that the black variety was not dominant, but 

 recessive to the type form, like the melanic variety oi Odontopera hidentata 

 (The Scalloped Hazel) investigated by Bowater^ More recently, Porritt^ 

 has published the results of some breeding experiments. In 1906 he 

 obtained "a considerable brood," from a mating oi varleyata x varleyata, 

 all of which proved to be like their parents. Further, in 1907 he 

 obtained a pairing between varleyata % x grossulariata (^ . The latter 

 was a typical wild insect, and 9 cTcT and 5 $ $ resulted, all of which 

 were like the male parent. With a view to testing this conclusively, a 

 strain of varleyata was procured by the author from Mr L. W. Newman, 

 and both the Rev. G. H. Raynor and Mr Porritt with great kindness 

 furnished some ova. 



1 Porritt, G. T., Ent. Mo. Mag. Vol. xli. p. 211, 1905. 



- Bateson, W., MendeVs Principles of Heredity, 1913, p. 44. 



3 Bowater, W. J., Journal of Genetics, Vol. in. p. 299, 1914. 



* Porritt, G. T., Ent. Mo. Mag. Vol. xliii. p. 12 and p. 276, 1907. 



