418 BRITISH LEPIDOPTEEA. 



in Kent in September, when the bulk of the imagines have appeared 

 in late July and August, and have always supposed that such larvae have 

 fed up after perhaps commencing to sestivate (and hybernate) a second 

 time. Zeller notes also the capture of A. ochsenheimeri in Syracuse, 

 in April, and asserts that he took four small male specimens of the 

 same species on September 4th, near Talentino, and others on Sep- 

 tember 11th, near Ancona. These he supposed represented a second 

 brood. Girard met with fresh specimens of A. trifolii of both sexes 

 at Trouville-sur-Mer (Calvados) on Sept. 29th-30th, 1880, in a locality 

 in which the species usually occurs in June, and surmises that the fine 

 weather of September had caused their development as a partial second 

 brood. Fletcher has found that, in captivity, A. trifolii is to a very 

 limited extent double-brooded. From eggs obtained early in June in 

 the years 1892 to 1897 (both inclusive) he bred 11 specimens, all 

 from eggs of the years. He has further attempted to force on a 

 second brood, by putting the young larvae in a south window, where 

 they were exposed to the warmth of the sun, modified by whitened 

 glass, but without any result. With the exception of this evidence of 

 Fletcher's, that relating to second-brooded Anthrocerids is far from 

 satisfactory. Difference of altitude, and, above all, meteorological 

 conditions often affect the emergence of insects, locally. On the 

 other hand, many Anthrocerid species pass more than one year in the 

 larval stage, i.e., a large percentage of individuals of these species do so. 

 To such an extent is this habit developed in some species, that every 

 individual of some Scotch A. filipendidae, which Fletcher procured for 

 experimental purposes in 1896, in spite of their removal to Sussex, 

 after hybernating during the winter of '96-'97, hybernated a second 

 time during the winter of '97-'98. He has also had other Anthrocerid 

 larvte pass a third winter in that stage. 



The close alliance that exists between many Anthrocerid species 

 has led to cases of cross-pairing between some of them. It has been 

 recorded as occurring between A. filipend'ulae $ and A. aclrilleae 2 , 

 eggs obtained, larvae hatched, but failed to reach maturity (Guenee), 

 A. filipendidae and A. ephialtes (Treitschke), A. lonicerae and A. fili- 

 pendidae, A. filipendidae and A. hippocrepidis, A. filipendidae and 

 A. peucedani, A. trifolii and A. hippocrepidis (Boisduval), A. minos 

 and A. filipendidae (Villiers). Boisduval says {Icones, ii., p. 36) that 

 in this cross-pairing A. filipendidae is always one of the species, 

 although he had previously stated (Monog. des Zyyenides, p. 5) that 

 he had many times found. A. trifolii paired with A. hippocrepidis 

 (= A. transalpina). He further remarks that he has never been able 

 to obtain eggs from these cross-pairings to hatch, although he believes 

 it probable that some eggs do so in nature. Cross-pairing has also been 

 recorded between A. filipendidae and A. £r//'oZu by Weir, but Fletcher says 

 with regard to this : " Seeing the great difficulty of pairing A. filipendidae 

 and A. trifolii in captivity, I should want strong evidence, actual paired 

 specimens with history, before believing that they paired in nature, and 

 actually bred and labelled hybrids before believing in them at all." 

 Weir notes the possession of two hybrid trifolii x filipendidae taken 

 wild, but Fletcher has the specimens, and refers one to A. trifolii ab. 

 basalis, the other to, probably, A. hippocrepidis, St. Zeller concludes 

 (Isis, 1840, p. 137) that " the formation of Zygaenid species is not yet 

 at an end, because of the constant copulation of specimens of different 



