[ 205 j 



IX. On the Clasping -org cms ancillary to Generation in certain Groups of the Lepido- 

 ptera*. By Philip Henry Gosse, F.B.S. [Communicated by E,. McLachlan, 

 F.B.S., F.L.S.) 



(Plates XXVI.-XXXIII.) 



Head May 4th, 1882. 



Introductory Bemarks : Existing Authorities. 



1 HE lovely insects, of which I am about to treat, have been the objects of so much 

 ardent admiration and intelligent curiosity, so long have they been collected from all 

 regions, so many cabinets are filled with them, so many treatises have been written and 

 compiled about them, that one may well be accused of presumption in daring to 

 surest the existence of an uncultivated field of observation in their structure. Yet 

 I venture to lay before the Linnean Society a series of facts, yielded to my own examina- 

 tion in the study of these exquisite creatures, which, while they elicit interest and 

 admiration in an unusual degree, seem to me to have beeu hitherto almost unsuspected. 

 I refer to the complex apparatus with which the male Butterfly has been furnished for 

 the prehension of the female during the copulative function. 



In most of the families of the Bhopalocera the organs devoted to this purpose are more 

 or less patent when sufficient magnifying power is used; and these are often exceedingly 

 curious and exceedingly various. If the Papilionkhc have seemed less profusely supplied, 

 it is, doubtless, because in them the prehensile apparatus is concealed beneath special 

 organs (calces), which do not to the eye present any feature differing from the scale- 

 clad body. The family, moreover, is almost wholly Trans-European ; and thus, though 

 very conspicuous, they lie somewhat beyond the range of ordinary scientific inves- 

 tigation. 



I hope I am doing no injustice to my predecessors, in assuming these researches to be 

 new. The older authors have little more tban vague allusions to the existence of 

 auxiliary prehensors, and nothing, that I am aware of, concerning those of the Fquites. 

 Herold (1815) describes and figures f the "spoon-like" valves, and the "triangle- 

 piece " in Bieris Brassicce. Burmeister (1832) describes J the outer and inner valves in a 

 Hawk Moth. Kirby and Spence (1828) devote § a paragraph to the prehensors of the 

 class, but dismiss the Butterflies in a few lines. Siebold and Stannius (1848) assign || 

 to the prehensors of the Lepidoptera one fourth of one sentence. 



The most important contribution to the subject seems to be a memoir f read before 

 this Society by Dr. P. Buchanan White, December 21, 1870. This elaborate and very 

 valuable article, illustrated by more than 220 figures, might well seem to leave little 

 room for my researches, but for two reasons : — 1, he limits his studies to the Butterflies 



* A preliminary sketch of this article will be found In the Royal Society Proceedings, xxxiii. (18S1), pp. 23-2". 

 t Entwickel. p. xiii. pi. iv. t Manual, p. 216 (Eng. cd.). 



§ Intv. to Ent. iv. p. 579. 1 Anat. Inv. p. 462 (Amer. ed. |. 



*il " On the Male Genital Armature in the European Rhapalocera," Trans. Linn. ISoe. 2nd ser. Zool. i. p. ;:"7. 

 SECOND SERIES. — ZOOLOGY, VOL. II. oii 



