304 



THE WINGS OF MECOPTERA 



Merope tuber is an American insect. Although it is quite widely dis- 

 tributed in the Atlantic States, less than a score of individuals are known to 

 exist in collections. Professor Needham had the good fortune to collect 

 one at Ithaca; and I am indebted to him for an opportunity to study its 

 wings and to give a figure of the insect (Fig. 316). 



A striking feature presented by the wings is the presence of a minute 

 semicircular tuberculous appendage near the base of the inner margin of the 

 fore wing. It was this that suggested the specific name of the species. 



The wings of Merope tuber (Fig. 317), at first sight, appear to be quite 

 different from those of the typical Mecoptera. But when they are exam- 

 ined in detail it is found that, aside from the fact that they are less elongate 

 and that they bear an unusually large niimber of cross-veins, the only 



important difference is that the costal area 

 of the wings is broad and resembles this area 

 of neuropterous insects more than it does that 

 of Pan or pa. This resemblance is increased 

 by the presence of many cross-veins extending 

 from the subcosta to the costa and a smaller 

 nimiber of cross-veins between the subcosta 

 and vein R]. 



The presence of one or two accessory veins 

 on one or more of the branches of the radius 

 and the anastomosing of cubitus with the 

 adjacent veins, which were pointed out above 

 as characteristic of the Mecoptera, are also to 

 be found in this genus. 



In the Ithaca specimen, vein R2 of all 

 of the wings bears a single accessory vein. 

 In the specimen figured by Westwood, vein R2 bears two accessory 

 veins in the fore wing and only one in the hind wing. But Dr. Asa 

 Fitch, who had both sexes of this species, states in his "Fourteenth Report," 

 that both pairs of wings are liable to vary in the number of these branches. 

 In fact in his female specimen the fore wing of the left side and the hind 

 wing of the right side had each one more branch than the corresponding 

 wing of the other side. 



In the fore wing of the specimen taken at Ithaca cubitus and the first 

 anal vein coalesce for a short distance. Immediately after vein Cu separ- 

 ates from I St A, Cui extends transversely to the long axis of the wing and 

 anastomoses with vein M for a considerable distance. Vein Cui bears 

 one accessory vein on the right wing and two on the left wing. The anal 

 furrow is along the first anal vein. There are three anal veins, all 

 unbranched. 



Fig. 316. — Merope tuber, slight- 

 ly enlarged (Photographed 

 by J. G. Needham). 



