280 ME, P. H. GOSSE ON THE CLASPING-OEGANS 



undistinguishable. Under the microscope, the whole surface, after denudation, appears 

 pitted with very minute shallow depressions, each with a knob at the bottom. They 

 are arranged in transverse lines; and those of each line alternate with those of the lines 

 preceding and following it, but this by no means witli mathematical precision. These 

 pits are avcII known as the receptacles of the clothing scales. Possibly, indeed, they may 

 have a second use, even to afford hold for the saw-points of the male harpes ; and the 

 clogging scales, carried away by the latter, had been, no doubt, displaced by the saw- 

 teeth in securing their grip-hold. 



At the posterior margins of the seventh and eighth segments, these surface-pits appear 

 closer together and larger than in other parts of the female abdomen. 



The surface of the ninth segment, which consists of the valvules of the vulva, is 

 peculiar — not clothed with scales, but cloth-like, being composed of hairs nearly erect, 

 placed exceedingly close together, and, though very fine, so short as to be, in places, of 

 a length not more than five or six times their thickness, as may be discerned when 

 under the microscope we view the very edge of the rounded surface against the light. 



Now, though it is not improbable that these last-named parts, the exteriors of the 

 valvules of the vulva, may be the spots ordinarily grasped by the apj)roaching harpe- 

 tips, yet I can discern nothing iu the nature of their surface, nor in that of the proximate 

 surfaces, to distinguish one species from another — each surface, in one, exactly correl 

 sponding to the same surface in each of the other species, whose females 1 examined. 

 And so there is nothing, so far as I yet know, to account for the astounding variety in 

 the harpes of the males. 



Yet, if I see a number of keys, of very minute and elaborate workmanship, all different,! 

 I cannot doubt that every one is intended to fit some special lock, though I have not 

 examined the wards ; and this conviction is the stronger, the more varied, and the more 

 complex are the keys. We cannot withhold a hearty assent to the conclusion of one of 

 the most eminent of modern physiologists, who, speaking of these organs in the class of 

 insects generally, says, "They prevent allied species from producing bastards by adulterous 

 connexions ; for the hard parts of the male correspond so exactly with those of the 

 female, that the organs of one species cannot fit those of another"*. And Leon Dufour 

 speaks of them as " a guarantee of the conservation of types, and a safeguard for the 

 legitimacy of species" f . But I should like to see these axioms demonstrated. 



What anomalies remain to be discovered, I cannot guess by the closest scrutiny of 

 the lovely wings spread out in our cabinets. The strangest deviation from normal form 

 that has occurred to my notice, is the unvalved abdominal apparatus in the beautiful 

 Papilio Rector of India. It is most aberrant ; but what hint of this is conveyed by the 

 gay body and wings ? Who could conjecture, by looking over a cabinet, that Ascalaphm 

 and Helen/is are so alike in their genital armature, while Hector and Agavus are so 

 unlike ? 



On the Harpe-tvpes. 



As the harpe appears to be the leading organ in the prehensile apparatus, the ruosll 

 fully elaborated and the most varied, I attempt a grouping of the different forms of this 



* Siebold, Comp. Anat. § 354, note 2. f Ann. des Sci. Nat. i. (1844), p. 036. 



