136 DIPTERA OF NORTH AMERICA. [PART IV, 



Goniomyia and the typical Ur-iopter-ina. That Cryptolabis 

 belongs here will hardly be questioned. Cladura, with its five 

 posterior cells, looks exactly like ..the Limnophilina ; its re- 

 semblance would be complete if it had spurs at the tip of the 

 tibiae. 



Chionea has been hitherto placed at the end of the Tipulidse, 

 as an anomalons group, without any distinct relationship. The 

 strict application, of the characters upon which the classification 

 adopted by me is based, points out its place very clearly, 

 Chionea has no spurs at the tip of the tibiae, which would locate 

 it either among the Eriopterina or among the Limnohina. Its 

 distinct empodia and smooth ungues determine its location 

 among the former. If we compare Chionea with the European 

 TiHmicra pilipes we cannot but be struck by the analogies 

 between them ; the same incrassated male forceps ; the same 

 stout, hairy feet ; and even the anomalous structure of the an- 

 tennae of Chionea is foreshadowed in Trimicra in the abrupt 

 reduction of the size of the three last antennal joints. Chionea 

 has therefore to be placed next to Trimicra, and is closely 

 allied to Erioj^tera. 



The review of the genera of Eriopterina just given shows that, 

 upon the whole, this section is less homogeneous than any other 

 (except the Limnohina anomala). The link connecting some 

 of the genera, like Cladura, for instance, with the typical forms, 

 is apparently artificial ; a Limyiophila with the spurs of the tibiae 

 so short as to appear obsolete, would, to all appearances, approach 

 Cladura. The same remark may be applied to the Limnophilae 

 with four posterior cells, and Gnophomyia; the former may 

 have obsolete spurs ; they would then be hardly distinguishable 

 from the Eriopterina. Is the distinction between those genera, 

 based upon the presence or absence of spurs on the tibiae, the 

 expression of a real fact in nature or only an artificial sub- 

 division ? I believe this distinction to be a real one, although 

 I confess that it would be very desirable to discover some more 

 characters to support it. The male forceps of both Gnophonnjia 

 and Cladura is very different from that of most Limnoi)hilina ; 

 still, it would be necessary to show that it is more cognate to 

 the forceps of the Eriopterina. Here, as in many other cases, 

 the discovery of new forms may help to solve these difficulties. 



