ANZA. 339 
ANEA. 
Anea, Hiibner, Verz. bek. Schm. p. 48 (1816). 
Paphia, Fabr. in Til. Mag. f. Insectk. vi. p. 282 (nec Lamarck); Westw. Gen. Diurn. Lep. p. 317. 
Anca is one of the largest as well as one of the most characteristic of Neotropical 
Nymphaline, and it probably contains not less than 100 species, so far as our present 
knowledge extends. All of these, with the single exception of Anwa ops, which occurs 
on the northern side of our frontier, are found within the Neotropical Region, no less 
than thirty-five occurring within our limits. 
One of the most remarkable features in this genus is in the relative positions of the 
costal nervure of the primaries to the subcostal and its branches, the branches of 
the subcostal coalescing with the costal in various ways, independent slips passing 
between the costal and the margin. Prof. Westwood, with his usual care, has 
drawn attention to this feature; but the question which he raises of the relationship 
of these slips to the subcostal branches which they, to some extent, supersede, we are 
still unable to explain satisfactorily. Proceeding along the costa in most butterflies 
from the base of the primaries the first nervure that reaches the margin is the costal, 
then come the subcostal branches in their order (first, second, third, fourth), and then 
the subcostal itself, or, as it is sometimes reckoned, its fifth branch. In Anwa the 
subcostal branches all unite with costal, except the fourth, and there are two or three 
slips from the costal to the margin; these do not start from opposite the subcostal 
branches, but usually between them. It seems probable that the first of these slips is 
the termination of the costal, that between it and the second slip and the apparent 
extension of the subcostal is in reality the continuation of the first subcostal branch 
which passes abruptly to the costa as the second slip, the second subcostal does the 
same, and so on. If this be correct, the costal, which apparently runs the whole length 
of the wing to the apex, does not really do so, but for a considerable part of its length it 
is made up of the costal branches, which unite for some distance to separate again. Two 
other points require notice: in some species the first subcostal branch is atrophied, and 
does not reach the costal at all; in others the third subcostal branch is itself branched, 
_the upper limb reaching the costal, the lower running free to the margin. In this instance 
there are but three subcostal branches, and it is reasonable to suppose that the third is 
the third and fourth united till the subbranch separates. Against this supposed arrange- 
ment of the nervures is the fact that the costal presents no indication that it is thus 
built up, but it runs in a single tube uninterruptedly throughout its length to the apex, 
gradually diminishing in size without reference to the nervules it receives and emits. 
The arrangement of the nervures in the neighbourhood of the costa throughout the 
genus all partake of this tendency to anchylosis; but the variations are so many and so 
little in accordance with other characters, that we hesitate to adopt them for the 
purpose of dividing the genus into groups; but taking these characters in a primary 
