26 



The Prehensores of Male Butterflies. 



[Nov. 17, 



eye is arrested at once by a great mass of firm flesh, white like 

 polished ivory, projecting from the abdomen immediately under the 

 uncus: this is the organ which, from a prevailing resemblance in shape 

 to a boat, I call Sca/phium. Of its function I remain ignorant : yet, 

 since, in some species, it is most elaborately and formidably armed — 

 as in P. Macedon, Mayo, Thoas, and, most of all, Merope — with teeth, 

 and spines, and saws, I conclnde that it must serve for prehension ; 

 though the question, " How ? " is very difficult to answer ; and 

 though it very probably has other offices. 



There is a manifest organic connexion between the scaphium and 

 the uncus ; like that organ it is occasionally wanting ; but sometimes 

 the uncus is present when the scaphium is absent, and sometimes 

 the case is reversed. 



5. The Penis. — This organ should strictly form no part of my 

 subject, which is not the function of generation, nor the organs that 

 perform it, but certain prehensile apparatus that are ancillary to the 

 performance. The penis is a principal, not an auxiliary ; yet, as it is 

 essentially the centre, around which the whole armature waits and 

 serves, and as it forms so conspicuous an object in the grouping of 

 the whole, I could scarcely avoid representing it in the drawings, or 

 giving some account, at least of its varying form and position, 



Some curious phenomena, moreover, have occurred in the organ, 

 which seemed to me worthy of being detailed and figured. Particu- 

 larly the occasional development of a white pulpy tissue filling the 

 chitinous tube, and evidently very distinct from it ; and, in some 

 instances, the extrusion of this tissue from the orifice, as a columnar 

 or globular mass, which bears curious evidences of its having been 

 forcibly extruded, in a condition at least semi-solid, and by succes- 

 sive spasms. 



In some species, as the Oriental P. Coon and its allies, this organ is 

 excessively attenuated, and as excessively lengthened, so as protrude 

 far beyond the limits of the valves, when these are normally closed ; 

 and so as to be quite apparent in the cabinet, like a projecting fine wire, 

 with which one may readily take up and handle the specimen, as if it 

 were an inserted pin. 



All of these organs may, be studied together, and with unusual 

 facility, in Ornithoptera Bhadamanthus and in Pwpilio Merope; Plates 

 I and IY of this memoir. 



As the harpe appears to be the leading organ in the prehensile 

 apparatus, the most fully elaborated and the most varied, I have 

 employed its variations of form to cast into groups the species 

 treated. This grouping is not proposed, in any sense, as a natural 

 arrangement ; but as a help to reference, and as a means of compari- 

 son of the varying conditions of the organ. 



One of the results, not the least curious, of this grouping, is the 



