66 RHOPALOCERA. 
Hab. Costa Rica (Van Patten®); Panama, Santa Fé (Arcé), Lion-Hill station 
(M‘Leannan 1). 
This species may readily be distinguished from the Guiana H. piera by the absence 
in both sexes of the yellow clouding of the apical half of the secondaries—a character 
which prevails to a greater or less extent in all the local forms of H. piera except that 
found in South Brazil, which has received the name H. hymenca from Dr. Felder, and 
which is almost certainly the same as H. diaphana of Lucas. The latter name was 
bestowed upon an insect supposed to have come from Cuba; but we have no more 
reason for believing that it did so than we have for crediting H. nereis, also included 
in Ramon de la Sagra’s work, to the same island, neither having since been found 
there. In their paper on Costa-Rica butterflies ? Messrs. Butler and Druce called the 
species of that country H. diaphana; but as Lucas lays stress upon the outer margin 
of the secondaries of his insect being less angular than in H. piera, and on the 
absence of red in the same region, we cannot admit this identification, and prefer to 
adhere to the name bestowed by Mr. Bates upon a female from Panama, with which 
Costa-Rican specimens of the same sex are identical. 
Of the races of H. piera in South America, that found in Ecuador is perhaps the 
most nearly allied to H. macleannania, as in it we find the greatest development of red 
about the anal angle of the secondaries of the female. It has, however, the clear 
secondaries in common with the Brazilian H. hymenwa, and also the strongly marked 
submarginal band. 
Our figures are taken from Panama specimens, that of the female from Mr. Bates’s 
type. 
PIERELLA. 
Pierella, Westw. Gen. Diurn. Lep. p. 365 (1851), being Div. A, Sect. Il. of Hetera. 
Pierella, Butl. Cat. Sat. B. M. p. 108. 
In this genus the wings are opaque, and the males are distinguished by a small spot 
of peculiar scales near the inner border of the secondaries. ‘The tibia of the front legs 
of the male is slender and the tarsus as long as the tibia; in the secondaries the 
lower discocellular meets the median close to the origin of the first median branch ; the 
proximal segment of the subcostal is much shorter than the proximal segment of the 
median. The genus thus restricted contains thirteen or fourteen species, which are 
distributed over the forest districts of Tropical South America from Mexico to South 
Brazil, being very common in the valley of the Upper Amazon, which is probably the 
metropolis of the genus. Four species come within our limits, whereof one is found 
in Mexico and Guatemala, and the other three between Nicaragua and the Isthmus of 
Panama. 
1. Pierella luna. 
Papilio luna, Fabr. Ent. Syst. ii. p. 1097. 
