( viii ) 



added specimens of both sexes of the parent forms for com- 

 parison, and it will be seen that the cross-product (which 

 Standfuss calls S. emiliee) resembles a large S. pavonia rather 

 than a small S. pyri ; except that the sexual disparity in size 

 and colour, which is so marked in S. pavonia as compared with 

 S. pyri, is very little developed in the hybrid. In most of 

 Standfuss's specimens of this hybrid, some of the veins are 

 forked terminally. This it will be seen is the case with one 

 vein of the right fore-wing in the male exhibited. 



" The second form is a hybrid with a somewhat more 

 complex ancestry. It consists of three males and three females 

 of which the female parent is S. pavonia, and the male parent 

 a hybrid between S. pavonia, $ , and S. spini, Schiff , ^ , i.e. 

 the cross-product to which Standfuss has given the> name 

 S. bornemanni. The present form (called by Standfuss S. 

 schaufussi) is therefore, in the common way of reckoning, 

 three-quarters S. pavonia and one-quarter S. spini. Dr. 

 Standfuss's first attempt to rear it ended in failure, his speci- 

 mens all dying in the larval stage. Subsequent trials, however, 

 were more fortunate, and some examples of Standfuss's own 

 rearing are figured in the 'Entomologist' for 1900, PI. VII, 

 figs. 6, 7, 8. The six individuals I now exhibit were reared 

 from eggs kindly sent me by Dr. Standfuss in 1895, and are 

 some of the actual specimens mentioned in the footnote on 

 p. 189 (p. 5 in the 'Hope Reports') of the paper above 

 referred to. 



"Their history is briefly as follows : — 

 1895. 

 May 11. Eggs received from Dr. Standfuss. 

 ,, 23. Eggs nearly all hatched. Larvae black, hairy. 

 Fed on whitethorn. Show distinctly gregarious 

 habit. 

 June 3. Larvse undergoing first moult. Some in second 

 stage show a rather indistinct yellowish-brown 

 lateral line. They are still gregarious. 

 ,, 14. Larva? in second moult. In third stage still 

 black, but some have a yellow or orange lateral 

 line. 



