﻿THE GENUS ITHYSIA. 



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especially on the veins and before vein one. This thickening is 

 especially marked on the median line, and extends for a space 

 of 3 mm. at the costal end of the line. The directions of the 

 first and median lines call for little comment, but that of the 

 second hne is exceedingly important. It proceeds from the 

 inner margin, through the lower angle of the cell, to the fifth 

 vein, and then proceeds with a sweeping curve almost the exact 

 quadrant of a circle to the costa. In most specimens the median 

 line is much nearer to the second line than to the first. 



There is generally a white discal spot surrounded by a blackish 

 ring. The subterminal white band has a strong brown-black 

 suffusion before it, and a weaker one after. In a fair percentage 

 of the specimens the terminal suffusion is absent, and then the 

 insects assume a very different appearance. I call this form 

 ab. extincta. The same type of markings holds on the hind 

 wings, except that the first line is absent, and the median one 

 nearly so. The discal spot and pupil are clearly marked on the 

 hind wings. In all wings the vems tend to be outlined in dark 

 fuscous. The termina of all are quite rounded, giving us a 

 crescent of almost perfect shape as the outline of the fore wings, 

 and a semicircle for that of the hind wings. The thorax is 

 densely covered with almost white fur above, tending to brownish 

 below, and the patagia may be outlined in brown. The body is 

 dark brown, more or less densely covered with greyish hairs or 

 fur. The genitalia are very simple, but are quite satisfactory, 

 for they afford us excellent characters for separating the species. 

 The valves are very short for the size of the insect, i. e. when 

 compared with other members of the group. The upper margin 

 is concave, whilst the lower is slightly so for five-sixths of its 

 length, when we have a strong upward curve to the rounded tip, 

 giving the valve roughly the outline of a pruning-knife. The 

 costal ridge on the valve is wide, and iL slightly raised. 



The uncus is much the same as in the other species, except 

 that the point is longer. The gnathos (the broad chin-like plate 

 below the uncus) is wide, with a broad and slightly roughened 

 tip, and is notched at the base. Its surface is squamous. The 

 cedeagus is short and stout, whilst the vesica is provided with a 

 few claw-like cornuti. The tergite of the eighth abdominal seg- 

 ment is slightly thickened, and is divided into two lobes. 



I. iTALiCA, sp. n. — This species has been assigned to both 

 alpina and gnecaria by various authors, a fact that seems strange 

 until one is acquainted with the fact that very few of the older 

 authors possessed all the forms. The first author who dealt with 

 this form was Scriba (' Beitrage ' iii. p. 215 (1793)), who 

 imagined he was dealing with Sulzer's species, and used Roemer's 

 emended na,me "alpinaria" for it. In this he was followed by 

 Esper (Baud v. Heft 9) in 1803, Hubner in 1796, and later by 

 Duponchel. It is noteworthy that Esper's form was the darker 



