ON REARING PAPILIO MACHAON. 5 



It was beautiful to see them dashing backwards and forwards 

 over the open spaces, and at the same time to see Papilio 

 philenor slowly circling round in the openings among trees. I 

 noticed the latter kept to the trees, while the machaon avoided 

 them. 



The machaon laid sparingly on fennel in the garden where 

 the fennel was dotted about the rough grass. The larvae on the 

 fennel in the garden did not succeed in growing up, but dis- 

 appeared when they were about an inch long. I suspect birds. 



With reference to birds and machaon larvae, I experimented 

 by putting about one hundred and fifty three-parts-grown larvae 

 on Skimmia, which is growing in large clumps in the open. In 

 three days the larvae were all gone, and sparrows were seen 

 Hying away from the clumps. 



The extraordinary number of small birds in Essex must 

 surely be answerable for much of the present-day scarcity of 

 butterflies. In woods crowded with game-birds one can also see 

 a reason for the absence of many species of butterflies one 

 would expect to find. 



Second brood.— The first of the second brood emerged on 

 June 8th and all were out by July 28th and mostly set free in 

 the garden. Some remaining in the house laid large quantities 

 of eggs. There being so many larvae I allowed them to feed on 

 the growing plants in the house, and not, as hitherto, having 

 them fed in leno cages. When nearly full fed I transferred the 

 greater number to cages, as an easier means of collecting the 

 pupae. Here it is interesting to note that wasps cut holes in the 

 rather old leno, entered the cages, cut up larvae, and flew off 

 with suitable-sized pieces. Later I found Diptera emerging 

 from machaon pupae suspended in the cages. I removed some 

 pupae from the cages and put them in a protected box, after 

 having weeded out all those which appeared stung. In October 

 I found another batch of Diptera in the box. 



On December 1st I examined one hundred and seventy pupae 

 in the box and found them all stung, and with the parasitical 

 grubs in various stages of development. This was the end of 

 that brood. 



The parasite which destroyed all my machaon is a Cheleid 

 belonging to the genus Pyromelas, according to Mr. H. Eowland- 

 Brown, who kindly identified them for me. This seems to 

 show that these flies can lay their eggs in pupae of any age. 



One curious fact is that no machaon pupae of the first brood 

 hybernated in either 1910 or 1911. Those of 1910 were all of 

 foreign origin. 



Those of 1911 were partly of foreign origin and partly half- 

 breeds, having English mothers and foreign fathers. 



The English machaon were distinguishable from the foreign 

 by being of darker appearance. 



