( 510 ) 



White costal patch on iipperside of liindwing of male very 

 large, extending to base ; forewing with white streak 

 in cell and some large patches oa disc (females and 

 most males) ........ Species No. bi). 



White costal patch of hindwing not reaching base, creamy 

 white ; no streak in cell of forewing and no large 

 patches on disc close to cell ; or there is a large patch 

 in apex of cell . ........ h. 



Hindwing below with small white adiiiarginal dots . . Species No. 56. 



Hindwing below without white admargiual dots ; red snb- 



marginal spots thin Species No. 57. 



40. Papilio philenor L. (1771). 



Papilio Eques Trnjanus philenor Linne, Mant. Plant, p. 535 (1771) (America). 



Pajjilio Eques Trnjanus astinous Drury, Ilhislr. Exut. Ins. i. p. 21. t. 11. fig. 1. 4. (J and Index (1773) 



(New York ; Maryland ; Virginia). 

 Larrtias phitemir, Hubner, Verz. be!.: Schmett. p. 84. n. 858 (1818?); Scudd., Bull. E. U.S. tfc Canada 



ii. p. 1-241 (1889). 



cJ ? . A close ally of P. poli/damas, being more generalised than that species 

 in the preservation of a tail (in most specimens), and of dots on the abdominal 

 sternites, and more specialised in the development of metallic colours and in tlie 

 reduction of the markings of the upperside. 



The presence of white discal dots on the underside of the hindwing is also 

 a generalised character, wliich is still more in evidence in P. devilliers and zetes. 

 Comparing the forewings of pohjdamas and philenor a close agreement in the 

 phyletic development of the spots will be observed. lu both species the spots 

 in the aj)ical region are the first to disappear, being longer preserved on the upper 

 than on the underside, the apical area of tlie underside assuming a faded tint. The 

 posterior spots of the upperside, however, which in pohjdamas are always present, 

 while they are often absent like the anterior ones in philenor, are always smaller 

 than the respective spots of the underside, the latter spots being preserved when 

 those of the ui)iierside have disappeared. 



The develojiment in the markings of the hindwing is o]>posite in the two 

 species. In poli/damas the band of spots of the upperside remains comparatively 

 broad, in connection with the development of the spots of the forewing, the spots 

 being rarely reduced to narrow lunules. The corresponding spots of the underside 

 have been shifted towards the distal margin, and are reduced to more or less 

 narrow bars. In philenor, on the contrary, the spots of the upperside arc much 

 reduced, being sometimes absent, those of the underside being much larger. 



The preservation of a tail in P. philenor and the West Indian zetes (Haiti) 

 and decilliers (C'uba), and the occasional absence of the tail from Mexican 

 specimens of philenor, are significant facts worthy of special mention. If the 

 tail is a nseful appendage developed to give protection to the individual, the 

 projecting tail being taken hold of by an insect-feeder and breaking off, altbrding 

 the insect a chance of escape, as is the opinion of adherents of this variety of 

 Natural Selection, we must naturally conclude that in countries where there is 

 a greater number of tailed species the persecution of the insects must be more 

 vigorous than in districts wliich are inhabited by comparatively few tailed species. 



