276 RHOPALOCERA. 
borders—one, D. aganisa, being restricted to Mexico and Guatemala, the other is the 
widely ranging D. biblis, which occurs as far north as Nicaragua. 
Jidonis is peculiar in its coloration, being dark brownish black with a red submarginal 
band on the secondaries of varying width, recalling certain species of Papilio. The 
palpi are peculiar, those of the male having the terminal joint short and elliptical; 
this in the female is much longer and more slender. 
The costal nervure of the primaries is much swollen for nearly half its length; the 
subcostal emits two branches before the end of the cell; the upper discocellular is distinct 
and directed forwards ; the middle discocellular is curved and the lower atrophied in the 
middle ; the lower end meets the median nervure a little before the origin of the second 
branch. In the male there isa thickly felted patch of scales between the median and sub- 
median nervures of the primaries beneath, and a corresponding patch on the secondaries 
above between the costal and subcostal nervures. The front legs of the male have a rather 
long coxa, >% femur-+ trochanter ; tibia >} femur; tarsus (single-jointed) >4 tibia. 
Kyes smooth. Palpi in the male with a short elliptical terminal joint <4 middle joint ; 
in the female this joint is half as long again, more slender, and >¥% the middle joint. 
Antenne with 50 joints; the club, consisting of 15 or 16 joints, is slender. The male 
secondary sexual organs have a tegumen with a double point and some strong folds 
along the outer edges; beneath these and projecting as far is another point in the anal 
cavity ; the harpagones are rounded at their ends and hairy; at their upper extremity 
is a feeble incurved hook ; at the extremity of the abdominal surface is a detached piece 
having a blunt end with strong central bristles; it also has on either side a lobe 
terminating in a blunt point with strong bristles directed outwards; the penis is nearly 
straight. 
1. Didonis aganisa. 
Biblis aganisa, Boisd. Sp. Gén. i. t. 9. f.. 77. 
Didonis aganissa, Westw. Gen. Diurn. Lep. p. 406°. 
Alis fusco-nigris, margine posticarum externo valde sinuato, fascia fere recta, marginibus serratis, ab apice ad 
angulum analem coccinea; subtus pallidioribus, posticarum fascia intus pallide rosacea, maculis ad basin 
tribus et una ad coste medium coccineis. 
Hab. Mexico”, Oaxaca (Deppe, Fenochio); British Honpuras, Corosal (Loe) ; 
GuatEMaLa, San Gerénimo, Yzabal, Motagua and Polochic valleys (F. D. G. & O. S.). 
Boisduval first separated this insect in the ‘Species Général des Lepidoptéres,’ giving 
the locality “ Java,” which is obviously transposed for “ Mexique,” applied to Melanitis 
ceryx figured on the same plate. 
From Mexico D. aganisa spreads through Guatemala from the sea-level to an altitude 
of 3000 feet. In Nicaragua its place is taken by D. biblis, from which it differs in the 
red line of the secondaries running nearly straight from the apical to the anal angle, 
which in the other species follows the curve of the outer margin. 
