80 DIPTEEA. 



shape of antennae and face; whether the ungues of Litorhynchus are provided with 

 teeth or not, Macquart does not mention). Loew rejected Litorhynchus, and it is not 

 probable that the generic character is applicable to the American species of the group 

 just denned, but a final decision cannot be arrived at without comparing South- African 

 specimens. In the meantime I will call this group Stonyx. 



2. The second group, if it was not for the presence of three submarginal cells, might 

 be taken for the genus Hemipenthes, Loew ; it has the same colouring of the body and 

 wings, antennas of the same structure, and rudimentary pulvilli. 



A similar although perhaps not exactly parallel case is afforded by Anthrax ocyale, 

 Wiedem. (Nubia), which, according to Loew, is an Anthrax, although it has three sub- 

 marginal cells (cf Loew, Siidafr. Dipt. p. 223). This group I will call Isopenthes. 



Synopsis of the Species of Exoprosopa (in the sense of Macquart) hitherto described from 

 Mexico and Central America (including the New Species described below). 



In this synopsis the numbered species are those of which I have specimens before 

 me ; the other species are placed in brackets, without numbers. Anthrax orcus, Walk. 

 List &c. ii. p. 237, described as being from Mexico, is omitted, because the type in the 

 British Museum is labelled " Para." 



I. Four, sometimes even five, submarginal cells. {Hyperalonia, Rond.) 

 II. Three submarginal cells. 



A. Third joint of the antennae elongate-conical, with a more or less long style, separated 



from the cone by a distinct suture; distinct teeth at the base of the ungues. 

 {Exoprosopa, sensu stricto.) 



a. The pattern of the wings consisting of more or less distinct brown cross-bands. 



1. caliptera, Say; 2. pueblensis, Jaenn. ; 3. iota, sp. n. ; 4. rhea*, sp. n. 



b. No cross-bands on the wings, but merely a more or less broad brown anterior 



margin; sometimes with infuscated cross -veins. 

 a. First posterior cell closed. 



5. limbipennis, Macq. ; 6. procne, sp. n. ; 7. anthracoidea, Jaenn. 

 y8. First posterior cell openf. 



8. rostrifera, Jaenn. ; 9. filia, sp. n. ; 10. socia, sp. n. ; 11. pardus, sp. n. ; 

 [sordida, Loew, Cent. viii. p. 21. — Matamoros], 



B. Third joint of the antennae short, onion-shaped, with a very long style, not bisected 



by a suture ; no teeth at the base of the ungues. 



a. Proboscis long ; no rudimentary pulvilli. (Stonyx, gen. nov.) 



1. clotho, Wiedem. ; 2. clelia, sp. n. ; [Anthrax lacera, Wiedem. Auss. zweifl. 

 ii. p. 634.— Mexico] . 



b. Proboscis short, with fleshy lips ; rudimentary pulvilli. (Isopenthes, gen. nov.) 



1. blanchardiana, Jaenn.; 2.jaennickeana, sp. n. 



* Placed hypothetically in this group, the antennae of both my specimens being broken. 

 f This is the general rule ; I have seen a specimen of E. rostrifera where the first posterior cell was closed 

 on the margin and on one wing only. 



