TETANOCERA. 115 



able, and that therefore its distinctness from Tet. flavescens is not 

 quite certain. Should the identity of both species be proved, the 

 name of "flavescens" as being preoccupied must be dropped, and 

 that of Tet. arcuata adopted for the species ; should, however, 

 future observations prove their distinctness, it will then be time 

 enough to choose another name for Tet. flavescens. 



6. T. arcuata LOEW. and 9 Seta anteimarum albo-plumosa ; 

 thorax punctulatus ; alse confertim guttato-reticulatse ; femorse antica 

 basira versus fusca. 



Bristle of the antennse plumose with white ; thorax punctured, wings 

 densely reticulated with dark spots and limpid drops ; anterior femora 

 brown towards the base. Long. corp. 0.18 0.3. Long. al. 0.2 0.23. 



SYN. Tetanocera arcuata LOEW, Wien. Ent. Monatsch. Ill, 292. 



So similar to the foregoing that it is very easy to confound 

 them, and after the detailed description which I have given of Tet. 

 flavescens, it will be quite sufficient to point out the characters by 

 which Tet. arcuata differs from it. It is always a little smaller, 

 sometimes much smaller than Tet. flavescens ; its second antennal 

 joint, too, seems to be comparatively smaller and narrower, and the 

 small brown spots on the upper side of the thorax beside the small 

 dots, are distinctly smaller. The anterior femora are to a consider- 

 able extent brown at the base ; their tips as well as the base of 

 the posterior femora are not seldom very brownish ; the anterior 

 tibios are blackened to a certain extent, and the posterior tibias 

 have this color at their very tips ; the three last joints of the anterior 

 tarsi are blackish. 



Hob. Middle States. (Osten-Sacken.) 



Observation., The more specimens of Tet. arcuata I was able 

 to examine, the more it appeared doubtful to me whether Tet. fla- 

 vescens ought not to be taken merely for an exceedingly large and 

 pale variety of Tet. arcuata. . The only difference existing in the 

 structure is, as it seems, the somewhat smaller breadth of the second 

 joint of the antenna? in Tet. arcuata; this is a very trifling one, 

 and perhaps only a character belonging to smaller specimens. 

 The narrow arcuated band running over the posterior transverse 

 vein of the wings, by which the first specimen which I received 

 w.as distinguished, was either more indistinct or quite wanting in 

 the specimens sent to me afterwards. 



