The Hybrid BISTONIN^ 



By J. W. H. Harrison, B. Se. 



PRELIMINARY AND GENERAL FACTS 



The group of species, usually known under the generic name 

 Bïston (Leach) is just as much a " magazine " genus as the old 

 gênera Lycœna, Agrotis, Larentia, etc., in spite of the fact that it 

 contains but few species. 



Two of the species, hispïdaria and sfrataria, included by Stau- 

 dinger, are obviously intruders hère, for strataria is almost con- 

 generic with betidaria, whilst liispidana, although not exactly of 

 the same genus as Phigalïa -pedaria and P. titea, is very close to 

 them and has been named the type of the genus Apocheima (Hb.). 

 The relationship between stralaria and betularia, and also that 

 between hispïdaria and pedaria is, well marked in ail the early 

 stages, which only serve to emphasise the fact that hispidaria and 

 strataria cannot be forced into any natural genus which will 

 include the others, of which hirtaria may be regarded as a typical 

 or primitive form. 



As the type of the genus Bïston (I^each) was fixed as strataria, 

 it is necessary to find new generic names for the others. I hâve 

 previously pointed out {Entomologist, July iQio) that the follo- 

 wing are the correct generic names. 



