( -ifil ) 



immediately below the anus and above the i)enis, and becomes visible when the 

 valves are removed. The homology of these organs has been explained by Dr. 

 Peytoureau in his work entitled Contribution d I'ctude de la Morphologic, de 

 VArnmre (jinitah: des hisectes* and we therefore refer the reader to that work ; it is 

 here suffieient to mention that Dr. Peytoureau comes to the result that the valves 

 are lateral wings to the ninth segment, which itself becomes visible only by 

 dissection, and that the dorsal uncus and the ventral scaphium, between which the 

 anus is found, rei)resent the anal or tenth segment ; the penis, therefore, has its 

 position between the niritli and tenth segments. 



The uncus, scaphium, and the cake with the harpe are of classificatorv value, 

 and if we intended to explain here the complete morphology of the genital armature 

 of the Papilios we certainly should have to take all three organs as well as the penis 

 into account ; merely for the sake of simplifying matters we have restricted our notes 

 almost to the valce and harpe. 



The harjje of the Pajiilios is a fold of the iuuer sheath of the valve partly raised 

 to ridges, teeth, hooks, rod-like jjrocesses, etc., which are sometimes of rather a 

 complicated structure. We have generally given a figure of the harpe and valve as 

 they appear when viewed with the eye perpendicularly above the i)laue of the 

 valve, while the figures representing the harpe or parts of it are so drawn that the 

 planes of harpe and paper are the same. Very much depends on the jjosition in 

 which the eye is to the harpe, if the comjwrative study of these organs is to be of 

 any nse ; a curved or twisted ridge or process ajipears very difl'erent when viewed 

 nnder a different angle ; and hence we have endeavoured to represent the same organ 

 of the various species and subspecies in the same position, so that a comparison of 

 the figures gives an exact idea of the differences in the organs. 



1. Papilio machaon ; t f- 3V) to -l.S. 



This species occurs nearly all over the Palaearctic Region, inclusive of China 

 and Japan, and is found also on the Indian side of the Himalayas at hio-hor 

 elevations, as well as in the Nearctic Region. The lines of delimitation between the 

 Old A^'orld forms of P. machaon are veiy difficult to draw, in fact cannot be drawn, 

 as the forms overlap in characters. TJie most remarkable varieties are the summer 

 brood of the Japanese machaoti, and the subspecies from the interior of Sikldm 

 and the higher parts of Western China. As we shall have to describe and figure the 

 sexual armature of the various forms of P. machaon in another i)aper, we intro- 

 duce the species here merely because it is the only British representative of the 

 entire group, and therefore will enable the British entomologist to verify our 

 observations. 



The i-ahe of /'. machaon is of a triangular shajie, and, though somewhat 

 variable in outline according to the individual sjiecimens, does not present any 

 obvious differences in the specimens of the different subspecies. 



The harjie is a longitudinal fold lying along tlie ventral margin of the valve ; 

 it is distinctly raised and leans somewhat over dorsally. The basal half or so is 

 rcmnded and simple, whereas the apical half is compressed, with the upper free edge 

 •lenticulate, so that it resembles the blade of a saw (f. ;{»— 43, ventral view). The 



* Rcviic Jlioloijiqiie du JVonl VII. 1H!).5. The author trivcs on pp. 13 to 50 a list of works dealing with 

 the abdomen of insects. 

 t See note un p. -liiO. 



