Pap. Remus, _Fabr. Godart_, _Cramer_, 135, A, 136, A, and 386, A, B.--Pap. hypolithus, var. _Cramer_, 10, A, B, 11, A, B. One of the largest species, the expansion of the wings sometimes measuring nearly eight inches. The superior pair are black, with a slight greenish reflection, and having a broad greyish-white stripe running along each side of the secondary nervures. The inferior wings are dark grey on the surface, and of a shining white on the under side, the latter having a black sinuated border interrupted by seven irregular spots of golden-yellow diminishing in size as they approach the abdominal margin. In the female, which is the sex represented on the adjoining plate, the golden-yellow spots are much larger, somewhat wedge-shaped, and each of them, except the outermost, marked with a large oval black spot. The abdomen is bright yellow above, paler on the under side, and irregularly spotted with black; the head, thorax, breast, and antennæ entirely of the latter colour. The native country of this elegant species is the island of Amboina. GENUS PAPILIO. Passing from the Ornithoptera, which may be esteemed the chiefs and princes of their race, we now come to the Papilios, properly so called, some of which are scarcely inferior in their dimensions and imposing aspect. Such, at least, is the case with _P. Antimachus_ and _P. Antenor_, which besides their large size, partake of some of the other characters of the group just referred to, and thus form the passage from it to Papilio. But the great majority are of very inferior size, and many of them so dissimilar in aspect that they might be thought to afford sufficient distinctions for arranging them in numerous different genera. On a close examination, however, the species are found to be so intimately allied in all essential parts of structure, that the most judicious systematists have not attempted to separate them. Such authors as have followed an opposite course, Hubner for example, have proved by no means successful in establishing sub-divisions; and the only effect of such a proceeding is to encumber the subject with a number of generic names without eliciting a more philosophical arrangement, or one better adapted to aid the student. As at present constituted, the genus is compact and natural; and if it were broken up by attaching undue importance to very subordinate characters, no partial change would suffice; for any principle that might be thought to justify the establishment of one genus, would render it necessary, if consistently acted upon, to create not fewer than thirty or forty. One of the most obvious differences among the species is the presence or absence of a tail; but an arrangement founded on this circumstance, separates, by a wide interval, kinds which are in other respects most closely allied. Nay, the tail itself is often more or less developed in the same species, being sometimes distinct in the one sex while it