278 ME. P. H. GOSSE ON THE CLASPING-OTJGANS 



A curious variation lies in this circumstance, that, while the proper condition is that the 

 darker, more chitiuous side of the cylinder, that which terminates in the finger-point, is 

 uppermost, there are numerous examples in which this order is reversed, and that side 

 is undermost, as in several of the Omithopterce, P. Agamemnon, Agavus, and others. 

 More rarely this (normally) upper side is only partly turned round ; so that the odd 

 notion is suggested, that the penis has the power of turning round on its long axis at 

 the will of the insect. 



It is also variously subject to curvature, often simply arched, with the tip downward, 

 by the lengthening of the middle line dorsally — Mayo, Rhodifer, Polycaon; sometimes 

 with the tip upward — Pammon, Hesperus; sometimes to either side — Memnon, Ver- 

 tumnus, Agesilaus; sometimes it is thrown into a double (sigmoid) curve — Rhetenor. 



The form is ordinarily cylindrical and tubular — Pammon, Zalmoxis; sometimes 

 spindle-shaped — Podalirius, Agamemnon ; the upper (denser) line very frequently pro- 

 duced into a finger-like point — 31ayo, Nireus, Macedon, of varying length. The extre- 

 mities of the sides usually expand, so as to make a wide, very oblique trumpet-mouth — 

 Helenus, Erithonius, Ulysses; and sometimes project beyond the general level into distinct 

 lips, or a sort of prepuce, often corrugated — Erechtheus, Mayo. In P. Semperi the 

 expanded orifice is of extraordinary dimensions. 



In its structure the penis seems to be formed of two distinct tissues, often w r ell defined. 

 Tbat side of the length which is normally the upper is a cylinder of more or less dense 

 and polished chitine — Hector, Podalirius, which is lined by another tissue of soft, pulpy, 

 white matter, of shining surface. The former is often (not always — P. Sesostris) divided 

 along its underside throughout; and the white tissue then exceeds its bounds — Hector, 

 Macedon, Podalirius ; sometimes notably, Codrus. This white element has other very 

 singular developments, for particulars of which I must refer to my detailed descrip- 

 tions and figures, particularly the curious globe protruded from the wiry organ of 

 P. Doubled <t if i, and the still more curious and thought-evoking cases of Orn. Rlchmondia, 

 Haliphron, and Darsius*. 



The variety of position and direction assumed by this organ, as has just been described, 

 seems to imply almost unlimited freedom of motion upon its basis. Yet, now and then, 

 we discern surrounding and, as I presume, supporting and restraining ligatures. That 

 the seaphium seems normally to send, inward and downward, fleshy branches, which, in 

 certain cases — Bathycles, Mayo, Agamemnon (all which see for particulars), surround th€ 

 penis, I have already mentioned. In P. Erechtheus a thick white ligament rises from 

 the floor of the genital cavity, or from each of the chitiuous knobs which afford interior 

 hases to the harpes, and, thrown over the penis, not far from its tip, appear to bind it 

 downward. But I have seen nothing like this elsewhere. 



In P. Doubledayi and Rhodifer (and also, on De Haan's authority, in Coon) the lonf 



* In the great Asiatic Moth, Atiaeus Atlas, where the organ has exactly the same form and position, I find, <lurin>- 

 life, that the terminal tissue, which fills the expansion, is very definitely separated from the brown chitiuous waUlj 

 of the tube ; it is pellucid-white, soft, and pulpy. 



