364 DIPTERA. 
NERILUS. 
Nerius, Fabricius, Syst. Antl. p. 264 (1805). 
Two species of this genus are known to me from Mexico :— 
Antenne black; legs dark brown. . 7 we ee ee ee ee ee pilifer, Fabr. 
Antenne and legs yellowish-rufous . . . «© 2. ee 6 © © e+ ee es flavifrons, Big. 
1. Nerius pilifer. 
Nerius pilifer, Faby. Syst. Antl. p. 264.11; Wiedem. Aussereur. zweifl. Ins. i. p. 550. 4°; Schiner, 
Dipt. Novara Reise, p. 247. 47°. 
Hab. Mexico, Teapa in Tabasco (H. H. Smith)—Sourn America }~*. 
Three specimens (2 ¢, 1 2). 
2. Nerius flavifrons. (Tab. IX. figg. 16, ¢ ; 16a, head in profile.) 
Nerius flavifrons, Bigot, Ann. Soc. Ent. Fr. 1886, p. 372 ¢. 
Hab. Mexico !, Teapa in Tabasco (H. H. Smith), Northern Yucatan (Gaumer). 
Three specimens (1 3, 2 2), agreeing with Bigot’s description. The brownish 
rings on the femora are scarcely visible; in the male the abdomen has a reddish dorsal 
band. The length, measured from the root of the antenne to the end of the abdomen, 
exclusive of the genitalia, is 65 millim. (Bigot gives 9 millim.). 
. MICROPEZA 
Micropeza, Meigen, Lllig. Magaz. 11. p. 276 (1803). 
Of this genus I examined six Mexican species. With one exception (IM. nigricornis), 
they all have the first posterior cell closed and more or less petiolated at the tip of the 
wing. 
1. Legs uniformly rufous. . 2. 2. 2. 1 1 we ee ee ee 
Legs rufous, the femora with dark rings. . . . 3. 
2. Occiput shining black in the middle, yellow at the sides; thorax . 
blackish. 2 2. 2. ee ee ee ee ee ee ee eipitalis, v. A. Walp. 
Occiput and thorax rufous . . . . . 1... ee ee ee rtficeps, v. d. Wulp. 
3. Thorax blackish, without stripes. . . . . . . . . . . . + obscura, Big. 
Thorax with longitudinal stripes. . 2... 2. 2. ee ee | 
4. Antenne black: small species (length 4 millim.) . . . . . . . migricornis, v. d. Wulp. 
Antenne rufous: larger species (length 5-7 millim.). . . . . . 5. 
5. Thoracic dorsum with two median stripes and some markings on each 
side; pleure not spotted . . . . . . Joe ee ee Bilineata, v. d. Wulp. 
Thoracic dorsum with three median lines ; pleuree with numerous 
smalldots. 2... 0. ee ee ee ew ee ee ew ee Stigmatica, v. d. Wulp. 
