Lizars sc.
Rhipheus Dasycephalus. From China.
RHIPHEUS DASYCEPHALUS.
PLATE XXX.
Urania Rhipheus, Var. Cramer, Godart.—Rhipheus Dasycephalus, Swainson, Zool. Illus. Pl. 131.
We have copied the accompanying figures from Drury’s work on exotic insects, in order that they may be compared with those represented on Plate XXVIII. It will at once be perceived that they present numerous points of agreement, as well as very obvious differences, and when every consideration is taken into account, it is not easy to say whether they ought to be regarded as distinct species, or merely varieties of the same. Drury states that his insect was brought from China, and when the drawing was taken, it was in the possession of Captain May of Hammersmith; in all probability, however, it is now lost. The antennæ are described as black and knobbed at their extremities, and the hinder wings are without tails.
On the supposition that Drury’s figures accurately represent the insect as it appeared when alive, the only connexion which it has with Urania arises from the similar distribution of colours and neuration of the wings; in other respects it would be classed with the Papiliones. But this anomaly is certainly a remarkable one, that it should combine clavate antennæ, with an arrangement of the alary nervures exactly corresponding to an insect with which in other respects it is so nearly identical. There being no other example of such a peculiarity, and the insect figured by Drury never having been found since, we are naturally led to suspect that he has been, in some way or other, under error. We have no doubt, however, that his figures afford a faithful representation of the specimen from which they were taken, as the drawings were made by Moses Harris, whose accuracy in such matters is well known. But there seems good reason to believe that the specimen in question has been originally defective, and that improper means have been taken to supply its deficiencies. By supposing that the head of a genuine papilio had been attached, in order to supply the want of that part in the specimen, and give it the appearance of being complete (a practice which has often been followed by amateur collectors), we get rid of the greatest objection to its being considered identical with Rhipheus. The want of the tails is easily accounted for, these appendages being so brittle when dry, that they are seldom preserved except in specimens which have received the utmost care. In other instances Drury has erroneously represented species as destitute of tails; we recollect in particular Satyrus Philoctetes. We mention these circumstances as affording means by which it is possible to account for the peculiarities presented by Drury’s figure; but it is likely that different opinions will be held on the subject. The following are Mr. Swainson’s observations:—“If the imagination was taxed to invent, or to concentrate into one figure all that was splendid, lovely, or rare in the insect world, Nature would far exceed the poor invention of man by the production of this incomparably splendid creature; its rarity also is so great, that but one specimen has ever been seen. It is not, however, on this account only that we have been induced to copy this figure, but because its illustration will clear up one of the most intricate and perplexing questions that has hitherto impeded the natural arrangement of the Linnæan Papiliones, and even of the whole order of the Lepidoptera.
“The error of Cramer regarding Rhipheus has already been rectified. It will now be demonstrated that not only are the two insects distinct as species, but that they actually belong to different genera; Cramers being a Urania of Fabricius and Latreille, while Drury’s is a Papilio of the same authors. This is proved by the figures, and confirmed by the following words of Drury :—‘The antennæ are black, and knobbed at their extremities,’ in other words, clavate; while the palpi, as expressed in the figure, are so small as not to project beyond the head, where they lie hid among the frontal hairs; this also being a typical distinction of the Latreillian Papiliones. The figures in Drury’s work were all drawn and engraved by Moses Harris, well known as one of the most accurate artists that ever lived; as a remarkable proof of this, we find that he has not failed to delineate that peculiar neuration of the anterior wings which belongs only to the types of Leilus. A closer affinity therefore between Papilio and Leilus cannot possibly be imagined; while its remarkable hairy front points out its analogy, as an aberrant type in its own genus, to Chlorisses among insects, and Dasycephala among birds. So true it is that the natural system ‘illuminates with a flood of light’ every supposed anomaly, and reconciles facts apparently the most inexplicable[39].”
FINIS.
FOOTNOTES:
[1] See his eloge on Lamarck, of which a translation will be found in the Thirty-ninth Number of the Edinburgh New Philosophical Journal. To this memoir we have been chiefly indebted for the particulars of Lamarck’s life.