IN CERTAIN LEPLDOPTEEA 297 



takes conspicuously the form of a bird's skull. Ordinarily this part is clothed densely 

 with the common scales and hair-scales ; but, when denuded of these, it is seen to he 

 smooth (not polished), thin, pellucid, light brown, composed of a very firm and bony 

 chitine. There is no joint between the ventricose " skull" and the slender "beak," so 

 that the latter can move only as the whole segment moves ; but its acute point (as seen 

 in figs. 12 and 13) falls normally just between the two terminal plates of the harpes when 

 the valves are closed. The uncus is slender, wiry, dark brown, glittering, moderately 

 curved, its tip slightly spathulate, its rami coming to a point horizontally and verti- 

 cally at some distance short of the tip. 



ScapMum essentially as in P. Mayo ; but the sides are much less bulging, the keel not 

 pointed, and the black knobs behind the erect "teeth " are replaced by tufts of crowded 

 brown bristles, which much resemble those usually seen in the Ornithopterce, but are not, 

 as there, limited to a linear series on each side. What in Mayo I compared to the gun- 

 wales of a boat, are here flat triangular expansions. 



The penis is short, with a thin expanded orifice, shrivelled, showing no apparent 

 structure. 



Papilio Rhetenob, Westwood. (Plate XXVIII. figs. 11-16.) 



Valve of an outline resembling that of the outer half of a lemon, oblique, the ventral 

 edge bv much the longer ; exteriorly dull black, thinly clad with scales ; hair-scales 

 projecting in a wide and close fringe beyond the dorsal margin, augmented by a forest 

 of slender bristles springing from the interior, so that the actual edge of the valve 

 is here much concealed, except in oblique lights. Along the ventral margin the fringe 

 is thin, and composed almost wholly of bristles from the cavity. 



The harpe, viewed in situ, PI. XXVIII. fig. 11, is a long tubular rod of glittering 

 chitine, terminating in an oblique hatchet-shaped head, facing the dorsal side, and set 

 with strong bristles below. On carefully removing it from the valve, and changing the 

 angle of vision, we find the head to be much of the form of an American woodman's axe, 

 fig. 15. Its edge is of semioval outline ; and, under increased magnifying power, is seen 

 to be notched with teeth of excessive minuteness and of no great regularity, of which the 

 three combined lenses of a specially powerful pocket-glass revealed no trace. 



The uncus is nearly bill-shaped, with slight curvature, sharp-pointed, deep-bladed, the 

 summit crowned with close, tall, erect hair-scales ; the rami stout and broad. 



ScapMum large, with a deep vertically truncate keel, wide margins, on which 

 stand conspicuous " double teeth," the principal one of each pair being a tall recurved 

 spine. The white fleshy rami of the keel descend to form an investing sheath, whence 

 the penis protrudes to a great length, almost horizontally, yet in a sigmoid curve, ter- 

 minating in a finger-point above, and a triangular expansion with thin edges, below. 



Papilio Deiphontes, Wall. (Plate XXVIII. tigs. 17-19.) 



Valve of the same form as in P. Pihetenor, Proienor, &c, but peculiar in having the 

 cavity marked on both sides, towards the point, with a number of parallel ridges ; both 

 margins are broadly fringed. 



The harpe, in situ, bears a close resemblance to that of P. Polymnestor, a slender 



SECOND SERIES. — ZOOLOGY, VOL. II. 42 



