338 ME. P. H. GOSSE ON THE CLASPING-ORGANS 



penis. From the lower edge of each cheek descends a prominent high ridge, which (and 

 its fellow), the intervening menihrane heing arched, embrace without contact the penis, 

 sending forward on each side that singularly elegant heart-shaped bundle of white flossy 

 filaments which I have described above (see p. 311 supra, and PI. XXXI. fig. 7). These 

 heart-shaped bundles unite into one beneath the penis, and merge into a horizontal 

 floor of the sheath, which runs back into the cavity of the abdomen. Another less 

 delicate bunch of similar floss is given off on each side from the outer part of the curtain. 



P. Anchisiades. The scaphium-sides go back into the ridge of the curtain (as in Agca 

 memnon), and sheathe the penis. The scaphium-keel is slit vertically at the front, the 

 slit expanding upwards. It is equivalent to the same part in 0. Remus; but there is no 

 pentagon, it scorns quite aborted. The cheeks are rounded, polished, light brown, and 

 thus chitinous, with a tuft of very short and line aristae, seated on the inner curve, to be 

 detected only by very careful focusing against the light, but then indubitably. 



P. Maccdo,i. Here, again, as I find by several examples, the scaphium is much the same 

 as in O. Remus, only that the front portion of the check is hardened and pointed, and so 

 excised as to form the principal tooth. Behind this is a ridge, which runs in an inner 

 line; the aristae are set from the interior side of tin; tooth, all along the edge of this 

 secondary ridge. Viewed in front, the appearance much resembles that of 0. Remus; 

 but the pentagon seems reduced to a mere line, not (visibly) split. The three teeth 

 which I had described and figured, at the point of the united cheeks (see p. 319 supra, 

 and PI. XXXII. fig. 3), now no longer appeared; their semblance was probably illu- 

 sory. The descent to the curtain is normal. 



These repeated observations make it highly probable that throughout the genus 

 Papilio, as in Ormthoptera, the scaphium has consimilar relations with the surrounding 

 organs, that it is constructed on a common plan though subject to many variations in 

 details, and that it is throughout composed of three distinct portions, which probably 

 possess distinct functions. 



