291 



FAMILY CHARACTERS 



Larva. — General appearance as in Chironominae, the prothoracic 

 and anal pseudopods, anal dorsal papillae, and paired apical dorsal 

 blood-gills being as in that subfamily. Details of the structure of the 

 head are lacking in Thienemann's description, but his figure shows 

 that the shape of the head more closely resembles that of Forcipomyia 

 than that of Chironomus, the mouth opening ventred instead of on the 

 anterior face. The prothoracic spiracles resemble small warts. The 

 thoracic and abdominal segments are longer than broad, clearly dif- 

 ferentiated, and armed with numerous spinules. The prothoracic and 

 anal pseudopods are armed at the apices with curved spines as in 

 Chironomidae. 



Pupa. — The pupa is distinguished from pupae of Chironomidae 

 by the stout, short thoracic respiratory organs, which are covered with 

 minute warts, by the presence of small warts on almost the entire 

 body surface, and by the structure of the apical segment, which has 

 at the tip 2 rather long, slender, upwardly directed processes and 2 

 long slender hairs. 



Imago. — See key to imagines of Nematocera. 



HABITS OF EARVAE 



The larvae are found in swift-flowing streams, and have the same 

 food habits as those of Chironomidae. 



HABITS OF IMAGINES 



The imagines are very sluggish in habit and are rarely taken on 

 the wing. Nearly all the specimens that I have taken in Britain, where 

 Orphnephila testacea occurs commonly, were swept from grasses and 

 ferns on the overhanging banks of mountain streams. This species 

 occurs very rarely in this country. 



Tribe Oligoneura 



I have included in this tribe the superfamilies Cecidomyioidea and 

 Bibionoidea, while Brauer included only the former. The arrange- 

 ment may not be an ideal one, and probably some may consider the 

 superfamilies as belonging to separate tribes ; but to my mind they 

 have many characters that link them together, though not so closely 

 as is the case with the families in Polyneura. If, however, they 

 must be separated, I would associate neither of the groups with any 



