DIPTERA. 251 



MYXOSARGUS. 



Myxosargus, Brauer, Denkschr. der k. Akad. Wissenschaften in Wien, xliv. 2, p. 77 (1882) . 



1. Myxosargus fasciatus. 



Myxosargus fasciatus, Brauer, loc. cit. p. 78 1 ; Osten Sacken, on Prof. Brauer's paper, "Ein Versuch. 

 etc.," p. 6 2 ; Boeder, Ent. Nachr. 1886, p. 139 3 ; Willist. Trans. Am. Ent. Soc. xv. p. 254 4 j 

 Giglio-Tos, Mem. della Reale Accad. delle Sci. di Torino, (2) xliii. p. 109 5 . 



Hab. Noeth. America, Georgia 3 , North Carolina 4 , Texas 2 . — Mexico (Sumichrast 5 ), 

 Atoyac in Vera Cruz (H. H. Smith), Orizaba (Bilimek, in Mus. Vind. Cces. 1 ). 



A single male specimen from Atoyac is somewhat doubtfully referred to this species. 

 The two pearly-white spots are at the tip of the frontal triangle. 



2. Myxosargus scutellatus, sp. n. (Tab. IV. fig. 18, $ .) 



$ . Head shining, greenish-black. Front in the centre with a small geminate tubercle ; a distinct transverse 

 depression below the middle. Antennas black, the first two joints yellow ; third joint divided into six 

 annuli, of which the first three are very short and closely united, the terminal annulus longer than the 

 preceding two together. Thorax black, clothed with delicate white pile. Mesonotum opaque deep green, 

 with feeble indications of coppery stripes. Scutellum wholly light yellow. Abdomen black, shining. Legs 

 black ; base of the four posterior femora and the distal portion of the front ones, all the tibiae except 

 a more or less broad ring, and the four posterior tarsi, save the distal two or three joints, light yellow. 

 Wings as in M. fasciatus. 

 Length 5-6 millim. 



Hab. Mexico, Teapa in Tabasco (H. H. Smith). 



Two female specimens. The present species differs from M. fasciatus, the female of 

 which is known to me only by the description, in the absence of the lateral tubercles 

 of the front, the wholly light yellow scutellum, &c. From the corresponding sex of 

 M. braueri, Willist., it differs in the smaller frontal tubercle, the shorter antennae, the 

 colour of the antennae and legs, &c. 



NEMOTELUS. 



Nemotelus, Geoffroy, Hist. Abregee des Ins. ii. p. 542 (1764). 



1. Nemotelus polyposus. 



Nemotelus polyposus, Say, Journ. Acad. Phil. vi. p. 160 (1829) 1 ; Compl. Wr. ii. p. 356 \ 



Hab. Mexico l 2 , Mexico city (H. H. Smith). 



Seven specimens, agreeing with Say's description. The last two joints of the tarsi 

 are black. 



2. Nemotelus unicolor. 



Nemotelus unicolor, Loew, Dipt. Centur. hi. p. II 1 ; Willist. Canad. Ent. xvii. p. 126 \ 



Hab. Noeth Ambbica, Illinois 1 , Pennsylvania 2 , Arizona 2 . — Mexico, Teapa in 



Tabasco (H. H. Smith). 



2k2 



