IN CEETAIN LEPIDOPTEEA. 285 



as it will go, the upcurved fingers representing the hooked teeth, and supplemented by 

 a ridge of teeth running obliquely across the wrist itself. 

 The uncus. — When the two valves are closed, as in life, the hand-like disks approach 

 udtther; and, between the facing rovrs of teeth, descends the point of the uncus. 

 This organ is not so wiry as in the preceding species, but rather suggests the blade of a 

 clasp-knife, projecting, with a wide triangular base, from the dorsal arch of the eighth 

 abdominal segment, having a moderately curved upper edge, and ending in a sharp 

 hooked point. What looks like the blade is truly the side of each of two vertical rami, 

 which, supporting and strengthening the structure, pass off laterally into the walls of the 

 segment. The whole is formed of bard horny chitine, dense in texture, dark in colour, 

 and glittering in surface, even as are all the prehensile organs which form the subject 

 of the present memoir. Sometimes the edge of the uncus-blade has a conspicuous notch ; 

 but the minuter details of all the organs are not absolutely identical in different examples 

 of the same species. One example had a minute supernumerary point just under the 

 proper point ; in another, the triangular base, viewed vertically, was distinctly notched 

 on each side, just where it narrowed to form the blade. 



The scaphium is large and plicated, white, shining, firm, the keel always prominent, 

 but in some more than in others. As in 0. Amphrysus and Rhaclamanthus, the rounded 

 lobe on each side rises to a thin crest, divided into notches, each of which is crowned with 

 an erect bristle, rising above the level of the uncus. The horizontal point of this lobe, 

 somewhat condensed in texture, seems to represent the " double tooth " of other 

 species. The median groove receives the blade of the uncus, as into a haft. 



The penis, as usual in the genus, is large, and funnel-like at its extremity ; in position 

 it is reversed, the more chitinous side, which terminates in a finger-like point, being 

 downward. In one specimen, this organ displayed a remarkable phenomenon (which, 

 under modifications, has recurred to me since), which I cannot satisfactorily explain. 

 Even the unaided eye could discern a thick white mass, connecting the trumpet-mouth of 

 the penis with the inferior surface of the scaphium. I immediately introduced a drop 

 of water into the genital cavity, and allowed it to stand awhile. I then removed, with 

 absorbent paper, the superfluous moisture, and applied a considerable magnifying power. 

 The appearance now presented, I have depicted with great care, in PL XXVI. fig. 7. 

 A cylindrical column of soft, subgelatinous, mirk-white substance, of a diameter slightly 

 less than that of the expanse of the penis, had, apparently, risen vertically from the 

 interior of this organ, till it had come into contact with the scaphium, against which it 

 had flattened by the continued vis a (ergo. The lower part of this column was tinged 

 with the yellow-brown hue of the organ itself. The chitinous lips of the expansion 

 seemed to have been forced wider apart — split, in short — by the protrusion ; and, what 

 seems to me very suggestive, certain lines of very pale chitine-colour, agreeing in form 

 with the outlines of the chitinous lips, looked as if the lining membrane consisted of 

 several coats, and as if these had been protruded, successively, one after another, as the 

 white matter had been pushed out ! 



But, what is the nature, what the function, of this white jelly-like matter ? Is it an 

 integral part of the organ ? Is it a secretion from it ? Is it the semen, under novel 



