MICEODON. 3 



The specimens captured by Mr. Smith, all of which are males, agree with the one 

 described by me from the Isthmus of Tehuantepec ; 1 would amend the description of 

 that, however, by calling only the tarsi black, and the femora and tibise deep blue. In 

 all the examples before me the posterior part of the abdomen is coppery-red : in three 

 of them strongly so. In the specimen with the less cupreous abdomen the thorax is 

 of a deep purple colour. Wiedemanns description does not apply quite so well as that 

 of Macquart. There are either a number of closely allied species or well-marked 

 varieties of the same species, and some doubt of the identity must remain till specimens 

 quite alike are compared from Brazil and Central America. Whether the example 

 from Brazil with yellow tibise mentioned by me 5 is of this species, I am, after com- 

 parison of the specimens, unable to say. It is quite certain that this is Walker's 

 M. trochilus. 



2. Microdon gracilis. 



Microdon gracile, Bigot, Ami. Soc. Ent. Fr. 1883, p. 320 '. 



Hab. Mexico \ Orizaba (H. H. Smith and F. D. Godman). 



Bigot's inadequate description will not permit any certainty in the determination, 

 but it seems not impossible that the single specimen before me belongs to this species. 

 There is a discrepancy between the diagnosis and description, as regards the antennse. 

 Our specimen has the antennse elongate, black ; the face with light yellow pile above 

 and on the sides ; the front with black pile, and its least width (male) scarcely less 

 than the distance from the foremost ocellus to the antennae. The scutellum has two 

 stout, moderately approximated, spines. The femora, and terminal joints of the tarsi, 

 are black. The wings have the cross-veins narrowly clouded, but I do not see " deux 

 petites macules diffuses, brunatres, au bord externe.' , 



3. HHicrodon baliopterus. 



Microdon baliopterus, Loew, Centnr. x. no. 56, in Berl. ent. Zeitschr. 1872, p. 86 1 ; Willist. 

 Synopsis N.-Am. Syrphidte, p. 5, t. 1. f. 2 \ 



Hab. United States, Texas 1 2 . — Mexico, Ainula in Guerrero 6000 feet, Teapa in 

 Tabasco (H. H. Smith), Temax in Northern Yucatan (Qaumer). 



The antennse vary in colour from red to black, and the tip of the abdomen is more 

 or less reddish. 



4. Microdon falcatus. 



Microdon falcatus, Willist. Synopsis N.-Am. Syrphidae, p, 9 \ 



Hab. Mexico, Tierra Colorada in Guerrero 2000 feet (H. H. Smith), Isthmus of 

 Tehuantepec l . 



I am not able to compare the type-specimen, and cannot say with certainty that my 



h 2 



