68 



COXNECTICUT GEOL. AND NAT. HIST. SURVEY [Bllll. 



(1925) and Christophers and Barraud (1926) on PMehotomus^ and! 

 Snodgrass (1903) on the Tipididae. 



The best paper on the oenitalia of male Diptera is that of Cole 

 (1927), who has described the genitalia of most of the dipterous 

 families, while Muir (1923), Smirnov (1925), and Wesch6 (1906) 

 have discussed the parts of the males in a number of dipterous types, 

 and Snodgrass (1935), Crampton (1923-1941), and Newell (1918) 

 have coinpai-ed the genitalia of male Diptera with those of other 

 insects. Discussions of the male genitalia in smaller groups of Dip- 

 tera will be found in the papers of Brolemann (1923), Liang (1926), 

 Meijere (1921), Snodgrass (1904 and 1935), Tokunaga (1930), and 

 AVesthof (1882), together with various papers by Alexander, Ed- 

 wards, and others on the Tipulidae; Christophers, Shortt and Bar- 

 raud (1926), Feuerborn (1922a), Friele (1930). and Perfilieo (1928) 

 on Phlehotomus; Oka (1926) and Tokunaga (1932a) on the Chiro- 

 nomidae; Christophers (1915, 1922, and 1923). Dvar (1918), Ed-, 

 wards (1920b), Freeborn (1924b), Martini (1922). Koot (1924), 

 Essig (1942), and Frost (1932) on male mosquitoes; Gibbins (1935) 

 on male Simuliidae; Bromley (1926) on Tabanus; Snodgrass (1902. 

 and 1904b) on Asilidae and Dolichopodidae ; Metcalf (1921) on malei 

 Syrphidae; Hennig (1934) on the jSIicropeziclae ; Sulc (1928) on thei 

 Sepsidae: Huckett (1924) on the Anthomyidae: Dinulescu (1930) on. 

 Stomoxys] Hewitt (1914) on Musca: Pint"o (1931) and Patton (1932- 

 1935) on various Muscidae; Bruel (1897), Rohdendorf (1926), and 

 Schraeder (1927) on Go2liphora\ Baronotf (1927), Mueller (1922- 

 1926), Petzold (1927). and Rohdendorf (1927) on the Tachinidae; 

 Boettcher (1912-1913)'. Aldrich (1916), and Parker (1914) on thei 

 Sarcophagidae; and ilote (1924), and Carpenter and Hewitt (1914) 

 on Ilypoderina. Figures of the genitalia of the males of various Dip- 

 tera are to be found in many of the recent monographs and descrip- 

 tions of new species, but these are too numerous to be included here. 



1. The principal landmarks of the abdomen 



The most important landmarks for identifying the parts of the( 

 abdomen are the location of the genital openings of the female and 

 male (with the twining ejaculatory duct of the male), the cerci and 

 anal opening, and the spiracular openings (with their distorted 

 tracheae) . 



'J'he position of the female genital opening, which is located be- 

 tween the sterna of the eighth and ninth abdominal segments (or 

 just liehind the eighth stern ite) serves to identify the eighth or geni- 

 tal segment of the female, while the location of the genital forceps, 

 and particularly the aedeagus. which are structures of the ninthl 

 segment, serves to identify the ninth or genital segment of the male. 

 Furthermore, the fact that the aedeagus, or male organ, is a sternal 

 structure, enables us to identify the ninth sternite when it becomes 

 inverted or displaced in the torsion process. The looping up of the 

 vas deferens and ejaculatory duct (Fig. 9a, A) from left to right 

 over the top of the hinclgut (which occurs in all male Cyclorrhapha) ■ 



