13 



an auriniid. The most distinctly athaliid of the American species 

 on the underside is nubinena, which is barely distinguishable from 

 aininia on the upperside, whilst linjfmanni and ir/dtnei/i are also 

 distinctly of an athaliid tendency on the underside, and also to 

 some extent, especially the latter, on the upperside also. Acastas, 

 a distinct auriniid, has some tendency on the underside to the 

 cinxiid group. There is, however, no actual member of the athalia- 

 group in America, and the existence of these species may imply the 

 persistence, in a latent condition, of those forces which in Europe 

 and Asia produced this latter group. 



With regard to the origin of the ciiucia-gvon^ I can only state the 

 facts as far as I know them, and suggest possible lines on one or 

 other of which the solution of the riddle may eventually be found. 

 It may, however, be taken as almost certain that Asia is the home 

 of this group, and that it has spread westwards in the case of the 

 romanovid section at any rate, though eastwards as well as west- 

 wards in the case of the cinxiid section, whatever their origin might 

 have been. Two of the species, pluebe and Jidt/nia, are exceedingly 

 wide in their distribution, extending from the Atlantic to the Pacific 

 and descending into the African, and in the case of didyma the 

 Asiatic, deserts, though not reaching very high in the mountains or 

 ascending very far north ; didi/nia, however, is more adventurous in 

 the latter direction than pluebe, and probably has the widest range 

 of all the Melitfeas. The range of ci)i.ria (even excluding perse) is 

 very considerable, but does not extend so far in any direction, except 

 perhaps west, as didijina, nor so far south or east as jilurhe. 



There remain the few species which in North America seem to 

 take the place of the rt^/mZ/a-group, which I have called the icri>/hti- 

 group, which includes fulvia, ci/neas, and possibly one or two others 

 whose specific value is not determined. The peculiarity of this 

 group is the partial or complete loss of the bands of the underside 

 hindwing. I am strongly tempted to enlarge here on my favourite 

 theory of the possible inherent directions of variation in any group 

 or species, for this tendency exists strongly as an aberrational form 

 in the European species of the athalia -grou\), somewhat rarely in 

 athalia itself, rather frequently in southern parthenie, not unusually 

 in asteria, and to some extent in dictynnoides, but the subject is too 

 large to touch upon here, beyond observing that this group reinforces 

 what was said some lines back on the persistence of latent 

 tendencies. 



I must on the other hand, for the sake of completeness, glance 

 still further back into the history of past ages to see what we can 

 guess of the affinities of McliUra with other groups. It is generally 

 supposed that when the Vanessids aud Argynnids separated off on 

 either side of the Nymphalid stirps, the Pyrameids were the first of 

 the former to break off, in other words that the Pyrameids are the 

 oldest genus of the Vanessid line. If this is true, it would seem 

 likely that the Melitaeids are older than the Brenthids and Argynnids 



