14 



effected by forcing open a small circular lid at one end of the cocoon. The 

 insects as they came forth, were active and ready for flight." T. H. 1829. 



In Martin Lister's edition of " Goedart," 1685, is a very lengthy article 

 on the present species. In it he says " that he bred several ichneumons 

 from the caterpillars, and also a species of two-winged carnivorus fly " and 

 adds " it seems contrary to the usual course of nature, that from one and 

 the 'same animal an offspring of a different speciejs should be generated, and 

 that one and the same creature should procreate in three different way." 



The fly is Mxorista vulgaris. Another parasite Apanteles rubripes has 

 also been bred from it. Two other insects of the same order Hemiteles 

 fulvipes and Mesochorus aciculatus are again parasitical on Apanteles glomera- 

 tus, thus illustrating the old rhyme 



" Little fleas have lesser fleas 



Upon their backs to bite 'em, 

 And these again have lesser fleas, 



And so ad infinitum.'' 



This and the next species are the only British butterflies that can be 

 charged with committing any appreciable amount of damage to human food 

 and property. In the winged state indeed they are perfectly harmless, but not 

 so the hungry caterpillars. Sometimes they are so abundant as to deserve the 

 title of a plague of caterpillars. One of these plagues occurred in 1853 and 

 1854, at Rottingdean, in the County of Sussex, concerning which is an in- 

 teresting note in the " Zoologist," vol. 13, by the Rev. Arthur Hussey : 

 " For the last two years many of the gardens in this village have been infested 

 with caterpillars to such an extent that the cabbages have been utterly des- 

 troyed. When the time for changing to the chrysalis state arrived, the sur- 

 rounding buildings presented a curious appearance, being marked with long 

 lines of the creatures travelling up the walls in search of a suitable place of 

 shelter for undergoing their transformation. Among the myriads which 

 wandered in search of a resting place, very rarely one of them would stop 

 upon a wall exposed to the south or south-westerly winds. A great number 

 of them took refuge in a malt-house, from which they could not escape as 

 butterflies, the result being that for several weeks the malster swept up daily 

 many hundreds of the dead insects. Probably a very durable green die might 

 be obtained from the bodies of these cabbage-fed caterpillars, as years of wash- 

 ing have not effaced the stain of one crushed upon linen." 



Besides the Ichneumons previously mentioned, birds do much towards 

 diminishing the numbers of these devastating caterpillars, and in his "Lepi- 

 doptera Britannica " Mr. Haworth writes thus, " I once observed a large tit 

 (Parus majos) take five or six large ones to its nest in a very lew minutes. 

 In enclosed gardens, seagulls with their wings cut are of infinite service. I 



