OALYDXA. EURYGONA. 437 



Genus XVITI. EURYGONA. 



Erygona Boisduval. 

 Erythia, Euselasia, Eubner. 

 Erycina p. God'. 



Body robust : wings large, generally entire ; liind ones elongated, and considerably variegated beneath, generally with 



a dark spot near the outer angle. 

 Head short, transverse, slightly tufted between the antennae. 



£yes naked. 



Antcnncc very slender, nearly two thirds of the length of the fore wings ; articulations not very distinct, and 

 slightly annulated with white ; terminated by a moderately elongated club, gradually formed, slender, obtuse 

 at the tip. 



Labial Palpi very minute, compressed, not extending so far as the hairs of the face, clothed beneath with scaly 

 hairs ; terminal joint very small, conical. 

 Thorax elongate-ovate, thickly clothed behind with hairs. 



Fore Wings subtrigonate. Costal margin slightly arched ; apical angle rather obtuse. Apical margin rather more 

 than two thirds of the length of the costal, entire, very slightly convex. Inner mai-gin straight, and rather 

 shorter than the apical. Costal vein extending to the middle of the costa. Postcostal with tiiree branches: 

 the first and second arising close together, a little before the anterior extremity of the discoidal cell ; tliii-d 

 branch arising at a short distance from, and sometimes quite close to, the apex of the wing (e. g. in E. Euriteus 

 it is so small as to be almost obsolete). Upper disco-cellular vein obsolete : middle one very slender, arising 

 about the middle of the length of the wing, a little beyond the second branch of the postcostal, short, strongly 

 angulated at a little distance from its origin ; the angle throwing off a short sjjur into the discoidal cell, 

 directed towards the base of the wing ; beyond the angle the vein is considerably oblique : lower disco- 

 cellular rather longer than, but not so oblique as, the middle one, very slender, uniting with the third branch 

 of the median at about the same distance from its base as the length of the lower disco-cellular itself, closing 

 the discoidal cell almost at a right angle with the third median branch. The upper discoidal vein arises 

 close to, or at a short distance beyond, the extremity of the discoidal cell, forming as it were the continuation 

 of the postcostal vein. 



Hind Wings more or less oblong-ovate, sometimes elongate-triangular. Costal margin well arched. Apical 

 margin rounded, entire, or but very slightly scalloped. Costal vein extending about two thirds of the length 

 of the costa. Precostal short, its apex curved slightly towards the body. Postcostal vein liranching at a rather 

 short distance from the base. Upper disco-cellular forming the slightly curved base of the discoidal vein, and 

 arising at a short distance beyond the origin of the postcostal branch : lower disco-cellular not quite so oblique, 

 very slender, arising further from the base of tlie upper one, than the space between the origin of the postcostal 

 branch and the base of the upper disco-cellular, and uniting with the third branch of the median vein at a 

 distance from its origin rather less than the space between the first and second median branches, closing the 

 discoidal cell in rather an acute point. 



Fore Legs of the male densely hairy, and very short. Fore Legs of the female also very short, scarcely longer 

 than those of the male, and rather thick. Tibia about two thirds of the length of the femur. Tarsus about 

 equal in length to the tibia, densely clothed with scales ; terminated by minute claws. 



Four Hind Legs short, robust, thickly clothed with scaly hairs. Basal joint of the tarsus as long as all the rest 

 united, armed beneath with a few minute spines. 

 Abdomen slender. 



Caterpillar very short and thick, onisciform, thickly clothed with short hairs, with two long erect spines 



at the back of the head. 

 Chrysalis short, oval, obtuse, clothed with short hairs. 



The majority of the speciea of this well marked genus are very plainly coloured on the ui>per surface of the wings, a few only being 

 ornamented with broad shades of blue or purple. On the under side, however, they are much more variegated, especially on the hind 

 wings, being generally marked with one or more transverse stripes of different rich colours, the ai)ical portion of the wing being streaked 

 with the same tints, and gener.ally bearing a moderate-sized dark spot, often tinged with brilliant blue or purple near the middle of the 

 outer margin, in the space between the second and third branches of the median vehi. The hind wings vary in form in some of the speciea 

 in which they are conically produced at the extremity next the anal angle. Tiie very short third branch of the postcostal vein is the 

 most characteristic distinction of the genus. In a sjiecies allied to Gelanor the postcostal vein has four branches, the third arising con- 

 siderably nearer the apex of the wing than the tip of the discoidal cell, and the fourth very close to the tip. The same occurs also in a 

 species with the hind wings long and very much angulated at the anal margin. All the species are natives of South America, where 

 they appear to be extremely numerous. The caterpillar of E. Midas, according to Stoll, is brownish black, with a_ row of white dots 

 along each side of the back, and a fringe of white hairs on each side above the legs; the segment behind the head is furnished with a 

 tuft of red hairs. It was found on grass. 



