124 Appendix. 



house, where they copulated and laid eggs on rape. 

 The caterpillars fed on the living plants in the breeding- 

 house, and after pupation were divided into two por- 

 tions : 



A. Several pupae, kept at the ordinary summer tem- 

 perature, gave butterflies on July 2nd, having the charac- 

 ters of the summer form. 



B. The remainder of the pupae were placed on ice im- 

 mediately after transformation, and remained over three 

 months in the refrigerator (from July 1st till October 

 roth). Unfortunately most of them perished through 

 the penetration of moisture into the box. Only 8 sur- 

 vived, 3 of which emerged on the 2oth of October as the 

 winter form ; the others hibernated in an unheated 

 room, and emerged at the beginning of June, 1874. All 

 5 were females, and all exhibited the characters of the 

 winter form. Notwithstanding a pupal period of eleven 

 months, they did not possess these characters to a greater 

 extent than usual, and did not, therefore, approximate 

 to the parent form Bryonice. 



1 6. On June I2th, 1871, specimens ofPieris Napi,vzx. 

 JBry0nuB,wer captured on a mountain in the neighbour- 

 hood of Oberstorf (Allgauer Alpen), and placed in a 

 breeding-house, where they flew freely about the flowers ; 

 but although copulation did not take place, several 

 females laid eggs on the ordinary garden cabbage. 

 From these caterpillars were hatched, which at all stages 

 of growth were exactly like those of the ordinary form 

 of Napi. They throve well until shortly before pupation, 

 when a fungoid epidemic decimated them, so that from 

 300 caterpillars only about 40 living pupae were ob- 

 tained. These also completely resembled the ordinary 

 form of Napi, and showed the same polymorphism, some 

 being beautifully green, others (the majority) straw 

 yellow, and others yellowish grey. Only one butterfly 

 emerged the same summer, a male, which, by the black 



