858 CHARLES PAUL ALEXANDER 



Pupae 



1. Pronotal breathing horns very long, cylindrical, the tips split into divergent flaps. 



(Group Ulomorphae, p. 869) 2 



Pronotal breathing horns not elongate-cylindrical. (Group Limnophilae, p. 858) 3 



2. Abdominal segments with tubercles or spines only near posterior margins of segments. 



Ulomarpha O. S. (p. 869) 

 Abdominal segments with three or four pairs of blunt, naked tubercles. 



Pilaria Sint. (p. 872) 



3. Abdominal segments depressed, lateral margins flattened, carinate, segments deeply 



incised 4 



Abdominal segments not depressed nor incised; pronotal breathing horns bicolored. 



Dicranophragma O. S. (p. 861) 



4. Abdominal segments with rows of acute slender spines; pronotal breathing horns very 



short, semicircular in outline, bluntly rounded at their tips. . Phylidorea Bigot (p. 866) 



Abdominal segments without such slender spines; pronotal breathing horns short, broad, 



slightly compressed, tips a little pointed Lasiomastix O. S. (p. 863) 



Group Limnophilae 



Genus Limnophila Macquart (Gr. swamp + friend) 



1834 Limnophila Macq. Suit, a Buff., vol. 1, Hist. Nat. Ins., Dipt., p. 95. 

 1854 Phylidorea Bigot. Ann. Soc. Ent. France, p. 456. 

 1861 Limnomya Rond. Dipt. Ital. Prodr., vol. 4, p. 11. 



Larva. Form slender. Spiracular disk surrounded by five, or more commonly four, 

 lobes, the ventral pair the longer and fringed with long, delicate hairs. Anal gills four, not 

 conspicuous. Head capsule flattened, very dissected, with plates narrow. Mandible not 

 hinged, curved, chitinized, on cutting edge with a few acute or flattened teeth. Maxilla 

 with outer lobe produced into a flattened projecting blade. Antenna two-segmented, at 

 its tip with a short or elongate-oval papilla which is delicately sculptured. Mentum a 

 transverse chitinized crossbar which is finely grooved. 



Pupa.- Cephalic crest setiferous. Pronotal breathing horns usually small, flattened, 

 tips not split. Mesonotum convex or flattened above. Abdominal segments in some cases 

 armed with tubercles or spines. 



The genus Limnophila comprises a very extensive group of crane-flies 

 (more than one hundred and fifty species), which are found in most parts 

 of the world but are apparently more numerous in the temperate regions. 

 The adult flies seem to be closely related, but the immature stages are so 

 varied in structure as to make it appear that the group must be a hetero- 

 geneous one and the similarity of the adults a result of convergent evolution. 



The adult flies may be found resting on rank vegetation. Several of 

 the species (Limnophila ultima, for example) swarm in small groups of 

 from fifty to sixty individuals, copulation taking place in the air, as is 

 discussed more fully on page 711. 



