It should be borne in mind, however, that there are two distinct criticisms by Lefebvre, to the second of which Boisduval only alludes in the most general way, and does not meet, while Butler makes no reference to it at all. As far as regards the position of the tail, Lefebvre is unquestionably wrong (see Pl. I, fig. 10), although his fault is primarily due to the inaccuracy of the engraving given by Boisduval, an inaccuracy which is slightly accentuated in our copy of it (Pl. I, fig. 17). But by far the larger part of his paper is made up of a detailed argument, drawn from the position and character of the markings and from the direction of the nervures, in which he endeavors to prove, and in most cases really does prove (though he errs in some of his statements concerning the neuration), that these markings belong to the front and not to the hind wing. He argues, for instance, that the two oval dark spots are plainly traversed by the nervures of the hind wing, and therefore cannot belong to that wing; that the minute white spot apparently on the outer border of the hind wing is only half a spot and must belong to the fore wing, and that the markings on and near the costal border traverse both wings and must belong to the one to which they certainly belong in part, the front wing. To this Boisduval makes no sort of answer, and Butler, to judge from his silence in the matter, and the comparative illustrations he gives on a plate published subsequently,[M] considers it unproven. All of these writers are, however, entirely wrong in supposing that the under surface of the wings is exposed to view, and that the hind wing covers the front wing. Boisduval does not distinctly state this; but the whole tenor of his remarks shows that this was the view taken by him; and when Lefebvre says: “Si de l’œil on suit les bords de la seconde aile, qu’avec le Docteur je reconnais couvrir en grande partie la première,” no objection is offered in Dr. Boisduval’s response; nor does he demur to Lefebvre’s statement, when the latter speaks of the “face inférieure, celle que nous voyons.” As we shall show later, however, the upper surface of the wings is that exhibited on the stone, and the front wing almost entirely conceals the hind one; compare Pl. I, fig. 13, drawn anew from the fossil. In the same place to which we have just referred Mr. Butler adds the following remarks on the probable affinities of this fossil:[N] The true position of _C. sepulta_ is undoubtedly in the family _Satyridæ_; and, so far as can be judged from the beautiful figure in the “Annales,”[O] it is exactly intermediate in character between three nearly allied genera now existing, viz.:—_Neorina_, _Antirrhæa_ and _Anchiphlebia_, its more immediate allies being the commonest species in each of the above genera. Its characters are distributed between these three species as follows:—