l. Sargus 



DJPTERA. 231 



SARGUS (p. 23). 



Sargus ?, Osten Sacken, antea, p. 23 \ 



Sargus lucens, Giglio-Tos, Mem. della Reale Accad. delle Sci. di Torino, (2) xliii. p. 103 2 (nee Loew). 



To the locality given, add : — Mexico (Salle 1 2 ), Orizaba, Cuernavaca in Morelos, 

 Atoyac in Vera Cruz, Dos Arroyos in Guerrero (E. H. Smith), N. Yucatan (Gaumer). 



I do not doubt that the Mexican specimens before me belong to the species 

 mentioned by Osten Sacken, in which Giglio-Tos thought that he recognized S. lucens, 

 Loew, described from Cuba. I have, however, seen a specimen of S. lucens from the 

 Antilles, and find the two to be quite distinct, the first-mentioned not having a white 

 spot on the sides of the mesonotum. 



Among the males there is a marked difference in the shape of the abdomen: in 

 some it is very slender toward the base, and widened, spatulate distally ; in others 

 there is only a gradual widening from the base to near the tip. In the specimen from 

 Northern Yucatan, for instance, the second segment is nearly as long as broad, while 

 in a small male from Atoyac the second segment is cylindrical, and fully four times as 

 long as broad : in the former the abdomen is almost wholly without the metallic 

 green colour, but I can distinguish no other differences. Two males from Cuernavaca 

 are almost intermediate between the above-mentioned males, the second segment being 

 about twice as long as broad. Two other males, from Dos Arroyos, are of medium 

 slenderness, but are of much larger size, and have the hind femora and tibiae black in 

 the middle. Two females from Cuernavaca are of the size of the largest males ; they 

 have the abdomen brilliant purple and blue, and only a little narrowed basally, and 

 the hind femora, except the base and tip, the distal portion of the hind tibiae, and the 

 distal joints of the hind tarsi, black. These specimens all agree in having the wings 

 lightly brownish, occasionally hyaline, and none of them have any yellow on the 

 abdomen. Moreover, there is a white spot on the sides of the mesonotum that is 

 wanting in the true S. lucens. S. tenuiventris, Bigot, seems to be very like some of 

 our examples, except for the white spots on the abdomen. Macquart's and (especially) 

 Rondani's descriptions of 8. speciosus agree very well, except as regards the hind tarsi. 

 The thorax is green in the males, deep blue in the females. 



3. Sargus coarctatus. 



Sargus coarctatus, Macq. Dipt. Exot. i. 1, p. 203, t. 25. f. 2 1 ; Walk. List &c. v. p. 92 2 ; Willist. 



Traus. Am. Ent. Soc. xv. p. 249 3 ; Giglio-Tos, Mem. della Reale Accad. delle Sci. di Torino, 



(2) xliii. p. 122 \ ^4 



? Sargus notatus, Wiedem. Aussereur. zweifl. Ins. ii. p. 84&^. 



Hab. Mexico (Sumichrast % Amula and Teapa (H. H. Smith).— Brazil 1 5 , Chapada 3 ; 



1 Chili 1 . 



