894 Charles Paul Alexander 



found on all the continents and on many of the oceanic islands. The 

 species are rather small, are dull-colored, and are often difficult of exact 

 determination. 



The immature stages are spent in a wide range of habitats, described 

 on page 838 



The local species of the genus Dicranomyia may be separated according 

 to the following key: 



1. Wings with but one free branch of the media reaching the margin. [23d Rept. N. Y. 



State Ent., p. 211-212, pi. 27, fig. 5. 1908.] (Plate XXXI, 15.) . . D. whartoni Needm. 

 Wings with two free branches of the media reaching the margin 2 



2. Wings narrow, lanceolate; cell 1st Mi open; thoracic pleura with a brown longitudinal 



stripe. [Limnobia longipennis Schum. Beitr. zur Ent., vol. 1, p. 104, pi. 1, fig. 2. 



1829.] (Plate XXXI, 14.) D. longipennis (Schum.) 



Wings broad 3 



3. Sc ending opposite, or before or slightly beyond the origin of the sector 4 



Sc ending far beyond the origin of the sector 20 



4. Antennae with at least the basal segments pale 5 



Antennae with the segments dark thruout 9 



5. Cell 1st Ml open (cross-vein m lacking) 6 



Cell 1st Ml closed 7 



6. Prescutum with a single brown stripe; dorsal pleural appendage of the male hypopygium 



a short hook. [Proc. Acad. Nat. Sci. Phila., p. 211. 1859.] D. immodesta O. S. 



Prescutum with three brown stripes; dorsal pleural appendage of the male hypopygium 

 a long, saber-like hook, which is contiguous with its mate on the opposite side. [Proc. 

 Acad. Nat. Sci. Phila., p. 212, pi. 3, fig. 5. 1859.] D. gladiator 0. S. 



7. Pale yellowish thruout, only the tips of the tarsi and the eyes darker; in life the abdominal 



segments somewhat greenish. [Proc. Acad. Nat. Sci. Phila., p. 212. 1859.] (Plate 



XXXI, 22.) D. pudica 0. S. 



Brownish yellow, the antennae darkened at the tips; halteres brownish 8 



8. Halteres pale, the knobs infuscated; abdomen brownish yellow. [Journ. N. Y. Ent. Soc, 



vol. 8, p. 183, pi. 7, fig. 5. 1900.] D. isabellina Doane 



Halteres and abdomen brown. [Proc. Acad. Nat. Sci. Phila., p. 212. 1859.] 



D. diversa 0. S. 



9. Cell 1st Ml open; Sc far before the origin of Rs, due to the shortness of the latter which 



is about equal to the basal deflection of Ri+i 10 



Cell 1st Ml closed; Sc nearly opposite the origin of Rs, which is much longer than the 

 basal deflection of /?4+5 11 



10. Rostrum elongated, nearly as long as the head, brown; prescutum with a single dark 



brown stripe. [Mon. Dipt. N. Amer., part 4, p. 65. 1SG9.] (Plate XXXI, 16.) 



p. rostrifera 0. S. 



Rostrum much shorter than the head, light yellow; prescutum with three dark brown 



stripes. [Mon. Dipt. N. Amer., part 4, p. 66. 1869.] D. brevivena 0. S. 



11. Thorax shining black, the pleura with a grayish pruinosity. [Proc. Acad. Nat. Sci. 



Phila., p. 17. I860.] (Plate XXXI, 23.) D. morioides 0. S. 



Thorax not shining black; gray, brown, or yellowish brown 12 



12. Femora brown with the tips broadly yellow; wings marked with brown. [Limnobia badia 



Walker. List Dipt. Brit. Mus., vol. 1, p. 46. 1848.] (Plate XXXI, 20.) 



D. badia (Walk.) 

 Femora not banded with yellow; wings unmarked or nearly so 13 



13. aS'ci much longer than Sci, being nearly if not quite the length of the stigma 14 



Sci short, not more than one-half the length of the stigma 16 



