DIPT ERA 293 



M. Postscutellum very distinct, i.e., metanotum with a double 

 convexity, (including Dexiinae, Phasiinae, and Megapro- 



sopina3).p. 323 Tachinid^e 



MM. Postscutellum not distinct, metanotum with single con- 

 vexity. 

 N. Notopleural setae* (i.e., those just above the dorso-pleural 

 suture in front of the base of the wing) two in number; 

 hind coxae bare behind, above base of hind femur; in 

 most cases metallic greenish or bluish species, p. 321 



Calliphorid^e 



NN. Notopleural setas three or four in number, if with 

 but two, then arista either pubescent or bare; 

 species in most cases grayish with a more or less 



tessellated abdomen, p. 322 Sarcophagid;e 



AA. Parasitic flies in which the abdomen is indistinctly segmented (except in Braula) 

 and the two legs of each thoracic segment are widely separated by the broad ster- 

 num. Parasitic upon bees, Braulidae; upon bats, Streblidae and Nycteribiidae; 

 upon other mammals and birds, Hippoboscidae. p. 324 Pupipara 



Suborder ORTHORRHAPHA f 



The Straight-seamed Flies 



This suborder includes those flies in which the pupa escapes from the 

 larval skin through a T-shaped opening, which is formed by a lengthwise 

 split on the back near the head and a crosswise split at the front end of 

 this (Fig. 501), or rarely through a crosswise 

 split between the seventh and eighth abdominal 

 segments. The adults do not have a frontal lunule. 



The families included in this suborder are 

 commonly grouped in two series: the Nemocera and the Brachycera. 



SERIES I. STRAIGHT-SEAMED FLIES WITH LONG ANTENNA 



{Nemocera J) 



Family Tipulid^e 



The Typical Crane-flies 



The crane-flies are mosquito-like in form; but they are usually very 

 much larger than mosquitoes. The body is long and slender, the wings 

 narrow, and the legs very long (Fig. 502). This family includes the 

 larger members of the Nemocera but it also includes some species that 

 are not larger than certain mosquitoes. The most distinctive feature of 

 crane-flies is the presence of a transverse V-shaped suture on the dorsal 

 side of the mesothorax (Fig. 503). 



Crane-flies are seen most often in damp localities, especially where 

 there is a rank growth of vegetation; but sometimes they occur in great 

 numbers flying over meadows and pastures. In most cases their power of 

 flight does not seem to be well developed for they fly slowly, and only a 

 short distance at a time. Some species, however, sustain themselves in 



* See "An Introduction to Entomology" by J. H. Comstock, p. 784. 

 f Orthorrhapha; orthos (6p6s), straight; rhaphe (pa<f>r)), a seam. 

 | Nemocera: nema (vrj/jta), thread; (k«p<xs), horn. 



