114 RHOPALOCERA. 
and is generally distributed from Southern Mexico in the north to the Argentine Republic 
in the south, the metropolis of the genus being equatorial South America, especially 
the eastern slopes of the Andes of Colombia, Ecuador, and Peru. The genus is unrepre- 
sented in the West-Indian Islands. As now known it contains about fifty species; but, 
owing to the variation of many of these, the number would differ considerably according 
to the views of various entomologists. Within the limits of our region we find eight 
species, representing all but two of the groups into which Morpho may be divided. 
These two are:—the one containing the largest species of the genus, represented by 
M. hecuba, distinguished by their great size and by the margin of the secondaries being 
nearly entire, the end of the second median branch alone bearing a large lobe; the 
second group forms a subsection of that containing WW. cypris, and is represented by the 
delicate If. sulkowskii, the presence of which in Central America is very doubtful. 
The characters of the genus are well given in the ‘Genera of Diurnal Lepidoptera ;’ 
and as Morpho has no allies in the New World, we need not repeat them for the pur- 
poses of comparison. 
a. Wings rich brown, either uniform or suffused with grey; primaries pointed ; 
secondaries deeply dentated. 
1. Morpho theseus. 
Morpho theseus, Deyr. Ann. Soc. Ent. Fr. 1860, p. 213°. 
Morpho aquarius, Butl. Cist. Ent. i. p. 74°; Lep. Ex. p. 113, t. 41. f. 1°; Butl. & Druce, P.Z. 8. 
1874, p. 339 *. 
Alis anticis falcatis, posticis (presertim apud angulum analem) dentatis, supra lete brunneo-fuscis, triente basali 
argentatis, linea duplici fulva marginatis, serie macularum ejusdem coloris submarginali ornatis, anticis 
altera quoque interiore notatis; subtus ferrugineo-fuscis, colore dilutiore nubilatis, anticis tribus, posticis 
quinque ocellis ornatis. 
© mari similis, sed major et alis pallidioribus distinguenda. 
Hab. Costa Rica (Van Patten ?**), Caché (Rogers); Panama, line of railway 
(M‘Leannan).—Co.omsts }, Magdalena and Cauca valleys. 
Dr. Van Patten’s Costa-Rica specimens were described by Mr. Butler under the 
name of Morpho aquarius; and he subsequently gave a good figure of one of the types 
in his ‘Lepidoptera Exotica,’ which, however, represents a male and not a female 
specimen, as the insects now in our collection prove. Mr. Butler compares his species 
with M. theseus, and strongly expresses his opinion as to its distinctness from that 
butterfly. With a large series of specimens before us from all the localities mentioned 
above, we are quite unable to discover any constant characters whereby to distinguish 
the Colombian and Costa-Rican insects. A certain amount of individual variation 
exists in all species of this genus; and in this case we do not see that the limits of 
individual variation have been passed by any one of the series before us. Mr. Butler 
gives, in his comparison of Jf. aquarius and MM. theseus, a long list of differences, none 
