478 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1925 



taken by himself. Although he had failed to get them to pupate, 

 he had had the hirvu' nearly, if not quite, full grown. 



The color of the larva? he had was more or less lilac, this color 

 becoming more brilliant as the larvaj increased in size until it 

 might almost be described as violet. At this period they spun to- 

 gether the seed heads of the thyme, but he never succeeded in find- 

 ing them alive in the spring following. 



Mr. Farn wrote to Mr, F. W. Frohawk that the eggs laid by the 

 females under perfectly natural conditions are laid singly (he 

 found only one exception) and are inserted somewhat deeply among 

 the clusters of buds of thyme. He could not discover any eggs on 

 thyme in full bloom, and remarked it would seem that the buds 

 are chosen so that the hatching of the larva) and the opening of 

 the buds should be contemporaneous. 



In 1903 Mr. Frohawk wrote that from observations he had made 

 the preceding year he felt convinced that some connection existed 

 between the larva3 of Lycceiui aHon and the common yellow ant 

 {Formica -fiava) by the preference shown by the butterfly in select- 

 ing the thyme growing on ant hills for oviposition. 



From July 5 to 17, inclusive, he found L. arioii numerous. Dur- 

 ing this period he watched several females laying eggs and on 

 the last day saw four females laying their eggs on thyme blossoms 

 on the top of an ant nest. 



The thyme grew in patches among the short turf, which was 

 composed of the usual small plants which clothe the surface of 

 the Cornish downs, and with a few furze bushes dotted about, 

 and on the ant hills. But the plants selected were those growing 

 in the open and some distance from the furze bushes, and there- 

 fore fully exposed to wind and rain. 



Under every patch of thyme visited by the female butterflies 

 he found ants' nests. He also saw other females lay eggs on the 

 thyme growing on ant hills, and also on the thyme upon the turf 

 walls where ants are likewise in abundance. 



On July 29 he found two larvae, which he had raised from eggs 

 deposited on potted plants by several captured females, rolling 

 about together under the thyme blossom. On close exanunation 

 he found that the smaller one had seized the larger with its jaws, 

 which were buried in its side, and was apparently sucking it. 

 Upon pulling them apart he placed the victim under the micro- 

 scope and found a deep hole in its side, with the surrounding 

 surface shrunken and liquid exuding from the wound. He re- 

 marks that this conclusively proves the cannibalistic habits of 

 these larvae, which he had always suspected, as on previous occa- 



