The abdomen is stout, half as long as the hind wings, well arched, and the terminal segment (of the female?) half as long as broad, the segments provided with a latero-dorsal and pleural row of very small, vertically ovate, pale spots.
This genus differs from Thais ([Pl. III], figs. 2, 4) and the other genera allied to the swallow-tails in about the same degree as they do among themselves. It is closely allied to Thais in most particulars; the antennæ resemble those of Thais, more than they do those of other genera, if we except only Sericinus; in the form of the wings it lies midway between Thais and Archon; as to neuration the discoidal cell of the fore wings has the form seen in Sericinus, being broadest apically, while in Parnassius ([Pl. III], fig. 5), Thais and Eurycus it is largest in the middle; but it is shorter than half the length of the wing, while in Sericinus, as in all the other genera, it is considerably more than half the length of the wing; the tip of the cell is limited above, in most of these genera, by the vein closing the cell; that is, the inferior subcostal nervule originates beyond the tip of the cell; but in Thais it originates at the tip of the cell, while in Thaites the cell is limited by the inferior subcostal nervule and the vein closing the cell originates from it; in other particulars of its neuration it resembles the tailed Sericinus.
In design ([Pl. III], fig. 3) Thaites recalls none of the recent genera very closely. In the fore wings it approaches Thais ([Pl. III], fig. 4) rather than the others, and in the hind wings some species of Parnassius ([Pl. III], fig. 5). It has none of the eccentric spots of Parnassius and a darker ground than any of the modern types. It is wholly unprovided with the strongly marked crescentic spots of Thais, but in the position, form and arrangement of the principal markings rather recalls Archon. Excepting Eurycus and some species of Thais, no modern genera resemble Thaites in the extension of a distinctive pattern upon the hind wings to or nearly to the extremity of the cell. Whether any of the markings were accompanied by the brilliant spots often seen in Thais, Archon and Parnassius cannot be determined, but we may presume that they were not, since in these genera the markings are dark upon a lighter ground, while in Thaites they are light upon a dark ground,—a combination found among the Papilonid genera, only in some of the swallow tails.
In the markings of the abdomen, I do not know that we find anything parallel to Thaites among the Parnassians, but among the neighboring Equites there are similar examples of rows of small light spots on a dark ground. I have not been able, however, to examine this point carefully.
THAITES RUMINIANA Heer MS.
[Plate III], figs. 1, 3, 6-10.
Thaites Ruminiana Heer, Climat pays tert., trad. Gaudin, 205 (1861) [absq. descr.]; Sap., Ann. Sc. Nat. [5], Bot., xv, 343 (1872) [ibid.].
The wings were evidently dark with light markings. On the fore wings the first transverse stripe ([Pl. III], fig. 3) extends from the subcostal nervure, midway between its first divarication and the base of the wing, almost to the middle of the basal two-thirds of the inner border; it is slender, nearly equal and straight, the portion within the cell about four times as long as broad; the second transverse band is the largest, and lies midway between the first and the third, parallel to them, reaching from the subcostal nervure almost to the inner border; it is straight and equal, and the portion within the cell (which is half of the whole, although traversing the cell at its broadest part) is three times as long as broad; the third transverse bar is in the middle of the wing, smaller than the first and equally slender, extending from the subcostal nervure, just beyond the tip of the cell, almost to the upper median nervule; it is equal and straight excepting above, where it curves inward following the border of the cell; the outermost is broader and more irregular, depending from the first superior subcostal nervule and extending nearly to the upper median nervule, so that its exterior border just strikes the subcostal nervure at its divarication far beyond the cell; the inner margin is straight and the spot thus forms a transverse bar, straight and equal above the subcostal nervure, but with the outer border sloping away so that the lower extremity is twice as broad as the upper. The submarginal series of spots are of nearly equal size, the uppermost largest, the next two smallest; each set of three forms a nearly straight line, but all together they follow a strong curve which approaches close to the border in the lowest subcostal interspace, being separated from it by but its own width; above this they recede rapidly from the border, the outer edge of the innermost being next the fork of the second superior subcostal nervule; but below, the spots are parallel to the outer border and separated by about an interspace’s width from it; the upper spots are transversely broad ovate; the lower transversely subquadrate; apparently the fringe is exceedingly short and concolorous as in Parnassius.
The basal parts of the hind wing are almost uniformly dark, excepting that there is a paler suffusion in the outer part of the cell; beyond, the wing is clouded with darker, transverse, strongly curving, powdery stripes; the most conspicuous of these is one which crosses the wing a little outside the middle of the portion beyond the cell; it takes its rise in a darker spot, which borders the wing just above the tip of the upper subcostal nervure, and runs in a nearly straight line, widening as it goes, to the lowest subcostal nervule, where it reaches its greatest width, and scarcely narrowing curves around to the inner border a little before its tip; on the nervules it reaches further baseward and borderward. Between this belt and another similar but much less conspicuous band, half way between it and the tip of the cell, are enclosed circular pale spots, one occupying the entire width of each interspace below the middle subcostal nervule and a portion of the one above it; following the principal dark band are two alternating sets of dark and light, narrow, inconspicuous, transverse stripes, more or less confused in the middle of the wing, the dark bands broadening and deepening at the nervures, breaking the paler bands to a greater or less extent into broad transverse spots; the fringe appears to be as on the fore wings. Judging from the form of the last abdominal segment, and the great size of the abdomen, this specimen was probably a female. Length of fore wing, 25mm.; breadth of the same, 14·3mm.; length of antennæ, about 6mm.; breadth of antennæ in middle of stem, ·2mm.; breadth of antennæ toward tip of club, ·5mm..