250 Mr. S. H. Scudder on the 



observations will be detailed in full in Part xiv. of the 

 current series of Mr. Edwards's 'Butterflies of North 

 America,' reported that during the mating of the sexes in 

 Parnassius smintheus he saw a "scimitar-like" organ 

 working beneatJt the membrane which formed the pouch, 

 and apparently moulding the same from the interior into 

 the definite shape which it assumes ; and this organ, 

 which he believed to be no part of the genitalia proper, 

 worked with a piston-like action in each division of the 

 pouch, which yielded to its motion. This would seem to 

 be directly opposed to Mr. Thomson's statement regarding 

 the formation of the pouch in P. apollo, as given by 

 Capt. Elwes {l. c, p. 13), for he describes a membranous 

 sheet attached to the male body containing a green 

 fluid, covering the female pouch on the outside, and 

 forming a "mould in which the pouch is formed during 

 copulation." 



Mr. Edwards having placed in my hands abundant 

 dry material during the past winter, I soon reached a 

 conclusion which seemed to throw some new light upon 

 the matter, and perhaps to reconcile the apparently 

 contradictory statements of the two observers mentioned. 

 My dissections were almost entirely of specimens of P. 

 smintheus, but, as they left many points still unexplained, 

 I was anxious to examine living examples, which alone 

 could furnish an answer, and verify or disprove my con- 

 clusions. At Mr. Edwards's solicitation, therefore, Mr. 

 Bruce sent me last spring on several occasions living 

 males of P. smintheus from Colorado, and Mr. Wright 

 one lot of living males of P. clodius from California. 

 Unfortunately none reached me alive, excepting a single 

 moribund example of C smintheus, too far gone to be 

 useful ; and since the failure of this experiment leaves it 

 improbable that an opportunity for my examination of 

 a living male l^irnassias will soon occur, I venture to 

 publish my observations in tbe hope that some one more 

 favoured by position will be moved to further investi- 

 gation. 



The structure of the abdomen of the male Parnassius 

 is remarkable for having, as in the Eupla3id genus 

 Anosia, the sides of the eighth segment expanded and 

 posteriorly extended, forming a kind of false claspers 

 concealing the greater part of the genitalia proper ; in 

 P. 87Jiintlieu8 and P. apoUo embracing also the inferior 



