Synonymy of Antocha O. S. and Orhnargula Mik. 415 



euroiiean A. opalizans I find that in most of them that distance is 

 tlie same as in Mik's figure of Orimargula; my heliograph, taken 

 from an american specimen, happens to have it shorter. A moro 

 striking difference between the two figures consists in the course of 

 the auxiliary and first longitndinal veins. — In Mik's figure the two 

 veins are separated by a distinct interval and connected by a distinct 

 crossvein; the first longitudinal, within the stigma, forms a sinuosity 

 enclosing a small cell. It is barely possible that by dint of ma- 

 ceration of the wing in some chemicals, and its strong compression 

 afterwards between glassplates, Prof. Mik may have prodiiced such 

 an appearance; in such a case he should have mentioned it. The 

 dry specimens of the two species which I am able to compare show 

 nothing of the kind; they sliow the auxiliary vein, closely approximate 

 to the first vein, and gradually coalescing with it; both form a slight 

 thickening of the costa just above the stigma. In fresh specimens 

 of Antocha which I examined recently the course of the two veins 

 is more distinctly visible, exactiy as it is described and figured by 

 me when compressed between glassplates (1. c. p. 125, footnote). In 

 other words the characteristic course of these veins in both species 

 consists in their great approximation, convergency and final coa- 

 lescence; white the majority of the other Limnobina have these 

 veins more parallel, and more or less distinctly incurved at the 

 end towards the costa. The only analogous form of coalescence of 

 the first vein and the costa I found in Toxorrhina (as I mentioned 

 1. c. p. 126 at the top). The little sinuosity of the first vein within 

 the Stigma, as represented in Mik's figure, exists in Antocha also, 

 but it is much paler, more straigth and less distinct than represented. 

 I take it for a mere chitinized fold of the wing-substance rather 

 than for a Prolongation of the first vein. 



The anal angle of the wing of O. alingena is represented by 

 Mik as less square-cut than that of A. opalizans. This is correct; 

 the difference really exists between the two species, although in a 

 very slight degree. 



The most striking character of the wings, common to both 

 species, is their apparent glabrousness and opalescence. While, 

 in most Tipulidae, a good lens shows the microscopic pubescence, 

 these two species require, for the same purpose, a Compound mi- 

 croscope. I have stated in Mon. IV, p. 125 that it requires a 

 magnifying power of 150 to discover the pubescence on the wings 

 of A. opalizans. I renewed the experiment recently, and compared 

 the pubescence of the same species, with that of the wings of 

 Thaumastoptera. The latter pubescence belongs to the most delicate, 



