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APPENDIX 
brand on the other wing or on the abdomen. Where brands or tufts lie 
free on the surface of the wings, they are on the upper side, so that in 
this case, when the butterfly rests with raised wings, they are hidden 
between them. They never appear to occur on the under side of the 
hind-wings, or on that part of the fore-wings left uncovered by the hind- 
wings. The scales of the “ brands ” are usually placed very close together 
and therefore stand almost upright, and are fastened far more securely 
than the ordinary scales of the wings. After removal of the scales the 
patches are recognizable not only by the densely packed points of attach¬ 
ment of the scales, but the membrane is also as a rule more or less cloudy 
or even dark coloured. Not infrequently they are traversed by arborescent 
branched or net-like air-tubes. The tufts, manes or bunches of hair con¬ 
cealed between the wings, or between wings and abdomen, tend to erect 
themselves when the wings are opened out or drawn away from the 
abdomen. Possibly all the tufts which lie free on the surface of the 
wings may be also capable of voluntary erection; in Opsiphams cassiae 
the tuft lying in the middle of the cell of the hind-wings can be spread 
out into a complete hemisphere. 
By far the most common structure—a brand or tuft on the costal 
margin of the hind-wings, between the costal and subcostal [nervures], 
and covered by the inner margin of the fore-wings, occurs in such 
extremely different insects, 1 that inheritance from a common ancestor is 
scarcely to be thought of, for such inheritance would necessarily imply, 
not only that the structure existed in the male of the original ancestral 
form of all diurnal Lepidoptera, but that it has been lost by the majority 
of his descendants. But with almost equal right one would also have to 
ascribe to this original male the patch or hair-tuft on the inner margin 
of the liind-wing, which occurs in the Danoinae , Satyrinae , Morphinae , 
Brcissolinae and Nymphalinae, and in a kindred form in the Papilionidae . 
It is far more probable that the furnishing of the males with special scale 
brands and hair-tufts occurred at a later stage and independently in the 
several groups. An argument in favour of this is the great variety to be 
seen within the same family, or even in the same genus (Mycalesis). 
Whatever, therefore, these brands and tufts, scattered through the most 
widely separated groups of diurnal Lepidoptera, possess in common, must, 
since it can scarcely be traced back to a common source, be considered as 
an adaptation to some similar purpose. As to what that purpose is, not 
even conjectures have, as far as I know, been made public hitherto [1876]. 
Chance revealed to me the meaning of the brands and hairs in a single 
species, and I presumed that these structures would have the same signifi¬ 
cance in all, a presumption I have since been able to confirm by the study 
of several species belonging to different families. 
1 In Danainae (Euploea, Ithomia and their allies); in Satyrinae (Mycalesis , Bid) ; 
in Morphinae (Zeuxidia ); in Brassolinae (Opsiphanes) ; in Nymphalinae (Lachno- 
ptera ); in Pierinae ( Leptalis , Callidryas) ; and in Hesperidae (Caecind). — F.M. 
