f 177 ) 



foniis. This is indeed true ou lii'st siglit, and renders it necessary to explain our 

 iudividiial position concerning that question, the more so as the number of distinct 

 species has been so much decreased in this paper as compared with the number in 

 Felder's list. We carried out our researches in dividing first the six hundred odd 

 named forms of Palaearctic and Eastern Papilios into preliminary groups which 

 are characterised especially by difi'ereuees in structure, and whicli will partly stand 

 as genera in the final generic revision (Mox-group, /wcior-gTowp, etc.), then uniting 

 again those forms of each group which exhibit a rather great similarity in pattern 

 and the minor structural characters {enrypylus, lycaon, saUastius, eurypi/lidfs, axion, 

 Jason, mikado) into sections which mostly turned out to agree with " species," and 

 then finally studying comparatively every form of such a section in respect to the 

 extent of variation, with a special view to find a practical rule which might lead 

 us to delimitate the species scientifically, not arbitiarily, in the case of each Papilio. 

 When we examine the individuals reared from the eggs of one femaU in every 

 resjject, we sliall always find some characters by which one individual is distinguished 

 from the other ; the individual characters of a specimen are often very obvious 

 (P. memnon L., P. aristolockiae Fabr., P. ormenus Guer., etc.), sometimes however 

 perceivable finly by microscopical examination. If it were possible to lireed 

 generation after generation from the offsprings of a single _/(?»««/<■ under the natural 

 conditions of life of that locality where the first /ewrtfe had lived as caterpillar and 

 ])upa, the dift'erences of the specimens tluis obtained would show us the extent of 

 variation of the insect at that ]}eculiar place. This can practically not be accom- 

 plislied, and we have to content ourselves with the knowledge derived from breeding 

 of one generation of Papilios reared from eggs which were observed tn be deposited 

 by a specimen, or from caterpillars feeding together and being apparently the 

 offspring oi one female. The experiences already gained by rearing of Papilios, 

 though limited, can nevertheless very well serve as proof that the specimens flying 

 together at a certain place, and exhibiting no greater difterences among themselves 

 than we are accustomed to find among the individuals reared from the eggs of a 

 female, belong to the same kind of insect, to the same species. The breeding of 

 sjiecimens shows further tliat tlie variation takes place in such a manner that the 

 extremes are connected by intergradations, except in the case of melanistic and 

 albinistic specimens, and so-called " sports," which stand often (not always) 

 isolated among the rest of the individuals. This gradual variation from large-spotted 

 to small-spotted, from broad-banded to narrow-banded, from tailed to toothed 

 specimens, enables us iu most cases where there is no help by breeding to come to a 

 right opinion abont the extent of the variation of a Papilio species. If there is a 

 gradual chain of varieties from one extreme to the other, neither the extremes nor 

 the intermediate degrees of variation can be regarded as indicatitig specific distinct- 

 ness of the respective individuals. When we see that the Indian P. euri/pi/lus L. 

 varies in the same locality gradually from being provided with large submarginal 

 markings to having small spots, it is impossible that Moore's P. acheroii is anything 

 else but a representative of a certain degree of variation of that eunjpi/lus ; when we 

 observe that in the South Indian and Ceylonese P. sarpedon L. the first (post- 

 costal) spot of the median band on the forewings becomes more and more obsolete, 

 disappears altogether on one wing, while it is still traceable on the other, it is 

 illogical to regard the specimens without the spot as being specifically distinct 

 (P. fliermoduaa .Swinhoe) ; and when we further have o^ the South Indian and 

 Singhalese P. crino Fabr. a series of specimens from one place which show a 



