FAM. TORTRICID^ 6i 



the vvellknovvn cristana and hastiana; the usual checks on variation, viz. hereditary conservatism, adap- 

 tation to a particular protective tj'pe, and the need for recognition by other individuals of the species, 

 seem to be inoperative here, but there is also apparently some active influence directlv conducive, and 

 not at present understood. 



Geographical distribution of species. — Numerous throughout Europe, Asia, ;md Ame- 

 rica, elsevvhere practically or entirely absent; this is a curious distribution, and difftcult of explanation. 

 I interpret it as follows : the genus is by hypothesis ancient, and must have originated in the highlands 

 of Southern Asia, since (i) it assumes more diversified forms there than elsewhere, which is the surest 

 sign of antiquity (2), the existing forms which most nearly approach its presumed ancestor are found 

 there, and (3) theposition is central to the present area of distribution. Thence it spread over Europe 

 and Asia, and reaching America by the northern lands on both quarters, extended down the chain of the 

 Rocky mountains and Andes to South .America. The barrier vvhich excluded it from Australia (where 

 there are only three species. all Ceylon insects possibly of artiflcial ihtroduction) and Africa (vvhere 

 there is only one alleged species of Felder's, perhaps one of his frequent errors of localit}', as it has not 

 been verified) was perhaps the hot cliniate of the equator, as the constitution of the tjenus is essentially 

 temperate, and in hot regions it is practically restricted to considerable elevations. Its absence from Nevv 

 Zealand cannot be so exphiined, for (as I show in the Transactions of the Nevv Zealand Institute for 191 1) 

 a large part of the New Zealand Lepidopterous fauna is of Northern temperate type, and must have 

 equally made its way dovvn the chain of the Andes and thence by Antarctic lands to New Zealand. The 

 chief genera however which thus effected an entrance have larvae which feed characteristically on 

 grasses or lichens, and Peronea feeds characteristicall}' on forest trees ; I think therefore that probably 

 the absence of suitable foodplants in the Antarctic lands was in this instance the restricting cause. 



Larva feeding in roUed or spun leaves, occasionally in Cecidomyid galls. 



Foodplants usually trees and shrubs, sometimes low plants of the same natural o'ders. especially 

 Rosaceae, Salicaceae, Ericaceae, Cupuliferae. 



Qroup A 



1. P. aurolimhann, Zeller. Stett. Ent. Zeit. V0I.27, P- '^9' P'- '• f- 3(i866). S. America. 



2. P. holmiaiia. Linnajus, Syst. Nat. p. 532 (1758). N.&C. Europe, Asia Minor. 



3. P. foliana, Walsingham, 111. Ilet. Brit. Mus. Vol. 4, p. 3, pl. 61, N. America. 



f. 3,6^1879). 



4. P. caerulescens, Walsin;ham, Ann. Mag. Nat. Hist. (7), Vol. 5, p. 370 E. China, Japan. 



(1900). 



Staudiageri, Kennel, Iris, Dresden. Vol. i.3, p. 205(1900). 



5. P. loxoscia, Meyrick,Journ.Bombay Nat. Hist.Soc.Vol. 17, p. 735(1907). Ceylon. 



6. P. ^ararfwMHrt, Walsingham, Ann. Mag.Nat.Hist.(7).Vol.5,p.37i ( 1900). E. Siberia, Japan. 



7. P. caudaua. Fabricius, Syst. Ent. p. 65i (1775). N. &C.Europe, N.America. 



etniirgiinn, Fabricius, ibidem. p. 65i (1775). 

 effractana. Hiibner, Samml. Eur. Schmett. f. 175 (1800). 

 excavana. Haworth. Lep. Brit. p. 408 (1812). 

 indecorana. Zetterstedt, Ins. Lapp. p. 989(1840). 



8. P. /«si-ytoi,'-a<«,Wa singham, Ann.Mag.Nat.Hist. (7), Vol. 5. p. 377(1900). Japan. 



9. P. pretiosaua, Kennel, Iris, Dresden, Vol. i3, p. 208 (igoo). E. Siberia. 



10. P. exsucaua, Kennel, ibidem, j). 208 (1900). E. China. 



11. P. confaminana, Hiibner, Samml. Eur. Schmett. p. 142(1800). N. &C. Europe, Asia Minor. 



? reticulata, Strom, Det. Danske Wid. Selsk. Skrift. p. 83 (1783). 

 ciliana, Hiibner, Samml. Enr. Schmett. f. 171 (1800!. 

 obscurana, Donovan, N'at. Hist. Brit. Ins. Vol. 12, pl. 374, f. 2 (1809I. 

 dimidiana. Frolich, Enum. Tort. Wurt. n» 27 (1828). 

 rhombana. Stephens. III. Brit. Ent. Vol. 4. p. 170 (i835). 



