J. W. II. Harrison 



201 



Thf,s*» (H)rr%*lationH ran Ih' HinipliHctl and rrndfriMl innn» vivi<l hy the 

 npptMult'd Uiblo aiul K'^'M''** ^*'*^' bl'fnrr K'^'"K ^^rnr, it will pmvj* vi-ry 

 ludpful Ui j(ivt» a phylo^t'iu'ticnl tnM' of the H|H»rirH invdIviMl. 



Hofoiv pnK't'iMiin^ t«» t'lnphasisc the most siilimt it( tin* n-latiniiM 

 gniphirally. it will bo wril t«) rxpami ami «Iiici(lat<* tlu* points nftTHMi 

 to in {Mimgraph 4 above and plaod in the l.ust cohnnn of the appended 

 t-abular Htjitenient.. 



* Not roannl in the wimo season imd under the same envintnmcnt conditions an tlie 

 others. 



All of the Bistonine species, but more particularly the Non-Hoannioid 

 section, which is of more interest to us at the present junctun^, instead 

 of emerging from the pupae together in the spring following pu|>iition, 

 agree, inasmuch jvs jjercentages, varying with the species, persist in 

 lying over as pupae from two to eight winters. Of the species here 

 considerefl, Xi/ssid <jraecaria is the most notorious offender as it rarely, 

 if ever, emerges in the second year, but commences by providing small 

 detachments in the third yeai*, followed by similarly small instalments 

 each se;v.*^on up to the eighth. L(ippo}iaria is the next W()rst culprit; 

 a limited number appear in the second year, the remainder appearing 

 at intervals in the ensuing three years. Ni/ssia zonaria is extremely 

 erratic in the actual numbeis lying over, but all come out before the 

 thinJ spring; Poecilopsis isahellae is nnich the siime, whilst in Lycia 

 hirt(iH(0 and Pitecilopsis pomonaria nearl}' all are bred when expected, 

 a very few remaining unchanged until the third year. 



And the effect of hybridity is that the fui'ther the habit, in this 

 respi'ct, of the .second si)ecies in the cross from Li/cia, the greater the 

 acceleration in enu'rgence.and the nean-r its habit approaclns L. hirtaria 

 the less the state of ati'airs is altere(l, e.g. cross Lijcin hirtarKt and Xt/ssia 

 graeairid «tr L. /nrtarid and PttecUopsis Uipponarid and all emerge the 

 ' Except extreme northern races whicli were not employed. 



