174 



Rostrum and palpi black. Antennae black throughout; flagellar segments 

 oval with relatively short and inconspicuous verticils. Head dark brown, the 

 orbits broadly more grayish; anterior vertex wider than the first scapal segment. 



Pronotum dark brown. Mesonotal praescutum with a broad dark-brown 

 median stripe, the lateral stripes paler and ill-defined; lateral margins of prae- 

 scutum with a sparse yellowish pollen; scutal lobes infuscated; scutellum pale 

 medially, the sides weakly infuscated; postnotum testaceous brown, sparsely 

 pruinose. Pleura pale, sparsely pruinose, the sternopleurite a little darkened. 

 Halteres elongate, dark brown, the extreme base of stem paler. Legs with the 

 coxae and trochanters pale, the fore coxae in some specimens a little more in- 

 fuscated; remainder of legs dark brown, the tarsi passing into brownish black. 

 Wings with a faint brownish tinge, the stigma only a little darker; veins dark 

 brown. Venation: Sc short, Sci ending opposite or before the origin of Rs, Sc2 

 some distance from the tip of Sci, the latter alone longer than the stigma; Rs 

 about one-half longer than the outer deflection of JK4+6; m-cu at or before the 

 fork of M. 



Abdominal tergites dark brown, the basal sternites more yellowish; hypopy- 

 gium dark. Male hypopygium with the ninth tergite nearly transverse, the 

 lateral angles with scattered setae, the caudal margin on either side of median 

 line with a small circular area set with 6 to 7 long setae, the tips of which are 

 decussate at the median line. Basistyle very complex in structure, the mesal 

 face produced into a slender blackened rod that is slightly expanded at tip, and 

 a stouter lobe that is provided apically with dense ti^ts of long yellow setae ar- 

 ranged in rows. Ventral dististyle fleshy, the mesal face at base produced into 

 a long, slender rostriform appendage that is dilated on the cephalic face at base; 

 rostral spines two, placed beyond midlength of rostrum, subequal, straight, 

 their tips acute, the spines lying subappressed to the rostrum; remainder of 

 dististyle fleshy, setiferous. Dorsal dististyle a very gently curved chitinized 

 rod that narrows to the long acute tip. Mesal lobes of gonapophyses short and 

 low. Ovipositor with the tergal valves very small, slender, gently upcurved to 

 the acute tips. 



Habitat. — M assachusetts . 



Holotype, male. Lake May, Berkshire Co., altitude 1500 feet, July 1, 1925 

 {Alexander). Allotopotype, female. Paratopotypes, 3 males. 



By existing keys, the species runs to Dicranomyia halterata 0. S., 

 a larger fly with confluent praescutal stripes and a very different 

 male hypopygium. This interesting fly was taken in a sphagnum 

 bog, associated with other characteristic crane-flies that were indi- 

 cated on a previous page. 



