EXPERIMENTS IN HYBRIDIZATION AND TEMPERATURE. 11 



distinguished from that species by the absence of dark patch at 

 anal angle of hind wing, and marginal markings below being 

 without reddish brown. 



Lynton Villa, Sydney Road, Enfield. 



SYNOPSIS OF EXPEEIMENTS IN HYBRIDIZATION AND 

 TEMPERATURE MADE WITH LEPIDOPTERA UP TO 

 THE END OF 1898. 



By Prof. Dr. Max Standfuss. 



(Continued from vol. xxxiii. p. 348.) 



If we count all the secondary hybrids together, they amount 

 to two hundred and eighty-two, among which was the consider- 

 able number of twenty-seven gynandromorphic specimens, which 

 were divided over at least twenty broods. When we think that, 

 after careful calculation, the lamented and capable entomologist, 

 A. Speyer, came to the conclusion that there was only one 

 gynandromorphic specimen to every thirty thousand typical ones 

 in nature, and, to quote a special case, during the eighty years 

 during which my father and I have collected, only sixteen 

 gynandromorphic specimens have been taken in the open or 

 have been bred from material obtained thence, of which three 

 were hermaphrodite — it would be absurd to regard this high 

 percentage of gynandromorphic forms of these secondary hybrids 

 as a mere matter of chance. 



There must be a certain reason for this fact. Is it to be 

 sought perhaps in their hybrid origin ? 



We know, from the fine work on gynandromorphic Macro- 

 Lepidoptera of Max Wiskott, of Breslau, and 0. Schultz, of 

 Berlin, that, among all the hybrids thus far bred, there were 

 only ten gynandromorphic specimens. To this must be added 

 another, bred by me in 1897, from a pairing of S. pavoniag^ x 

 pyri ? , the only^^ one among more than two thousand primary 

 hybrids, which I have as yet bred. 



The percentage of gynandromorphic specimens among prim- 

 ary hybrids is without the slightest doubt infinitesimal, compared 

 with their occurrence among secondary hybrids. It is, however, 

 relatively higher than among individuals of pure origin, which 

 must not be lost sight of. 



The condition of all the female parents of these secondary 



j^Q A further gynandromorphic primary Saturnia hybrid developed in 

 1898 from a crossing of S. pavonia^ xspini^- The number of primary 

 hybrids bred by me is now increased to over four thousand, on account of 

 the large hybridization experiments with the genera Drepana and Pygcera , 



