SPECIES OF MYLACRIS. 803 



humeral lobe is prominent, it's straight basal side bent at nearly a right angle with the 

 arcuate costal edge, the angle rounded off"; the costal margin is considerably arcuate, 

 more strongly at extreme base and beyond the middle than in the intermediate straighter 

 portion where the arcuation is very gentle; in this respect the figure previously given is 

 slightly inaccurate. The course of this margin with tbe breadth of the wing; and the direc- 

 tion of the veins render it probable that the rest of the wing bad the form given in the 

 dotted lines in the figure, in which the apex of the wing falls within the middle line, and 

 slightly changes the form from what was given before, and which we had already noticed 

 as probably not correct. The veins originate from the middle of the wing and curve a 

 little at the base. The mediastinal area has a basal width of very nearly half the wing, 

 and, separated from the scapular by a scarcely curved line, strikes the costal margin at 

 about the end of the second third of the wing (in one specimen probably a little less than 

 that, in the other probably a little more) ; the basal part of the costal margin is very 

 narrowly and delicately marginate ; the part of the mediastinal area next the humeral 

 angle is not veined, but below it are four or five scarcely curving, long, gently diverging, 

 simple or deeply forked veins ; the mi Idle ones simple (possibly united nearer the base, 

 where they are not su ficiently preserved to see it), the others forked. The scapular vein 

 is gently and broadly sinuous and probably terminates just above the apex of the wing; 

 in the basal part ot its course it runs closely parallel to the costal margin and a little 

 nearer to it than to the inner margin ; in the latter half or more it curves in an opposite 

 sense to the costal margin ; it commences to branch very near the base, and emits four or 

 live branches, simple or forked, rarely compound, long and nearly straight, having the 

 same direction as the outer mediastinal veins ; in one specimen the basal, in the other the 

 apical vein is compound, the rest generally simple. The externomedian vein is somewhat 

 arcuate until it divides, a little beyond the basal third of the wing ; both these branches 

 again divide scarcely beyond the middle of the win"', the uppermost again forking not long 

 alter ; probably they fork more, and, as in the central part of the wings, (ill their area with 

 dichotomizing veins whose general direction is nearly longitudinal, with a slight down- 

 ward tendency, but closely approximated, so that on the edge the veins occupy a narrow 

 area mostly below the apex of the wing. The internomedian runs in a broadly sinuous 

 course parallel to the preceding vein, probably strikes the lower margin where the wing 

 begins rapidly to narrow, and emits four or live, perhaps more, simple or basally forked, 

 indistinct, arcuate branches, which occupy upon the inner margin about as much space as 

 the scapular upon the costal margin. The anal furrow is strongly impressed upon its basal 

 half or more, less so but still distinctly beyond, is composed of a pair of closely approxi- 

 mated fine grooves, and is regularly and not very strongly arcuate, terminating on the 

 inner border at some distance before the end of the mediastinal area, at just about the 

 middle of the border; the anal veins are numerous and closely crowded, nearly all simple, 

 and all slightly arcuate. 



It is a tolerably large species, tbe breadth of the wing being 13.5 mm. and its length 

 probably 2G mm. ; or, its breadth to its length about as 1:2; the actual length of one frag- 

 ment is 19 mm., of the other 2U.75 mm. ; the condition of the first is mentioned in the former 

 description of the species; the second specimen is represented both by that drawn and by 

 its reverse ; in the one drawn the veins are in relief and the figure represents, therefore. 



