EEISTALIS. 



61 



abdomen has an interrupted or subinterrupted, the fourth an entire, shining cross- 

 band. In the female the black of the second abdominal segment is somewhat greater 

 in extent, the red of the third segment is confined to the anterior angles, and the 

 fourth and fifth segments are wholly black, except the yellow hind margin. Macquart's 

 description of E. bogotensis x , from Santa Fe de Bogota, applies excellently well to the 

 female; v. d. Wulp's remarks (Tijdschr. v. Ent. xxv. p. 129), however, not so well. 



8. Eristalis trigonus, sp. iu, $ $ » (Tab. II. figg. 4; 4#, head.) 



Male. Eace amber-coloured, a median stripc, to above tbe tubercle, shiuing, above and on tbe sides densely 

 yellowish-polliriose and ycllow-pilose ; cheeks sbining black. Frontal triangle blackish in the middlc, 

 tbe pollen brownish and yellowish, the pile chiefly black. Antennce yellowish-red ; arista bare. Eyes 

 densely pilose. Mesonotum, beforo the suture, opaque brownisb-grey ; behind the suture opaque grey, 

 with three large opaque velvety-black spots— the median one elongate oval or suboval, the lateral ones in 

 the shape of a right-angled triangle, witb the hypothenuse gently concave. Pile of the mesonotum 

 yellowish-brown. Pleurfe densely grey-pollinose, blackish in the middle above ; pile yellow. Scutcllum 

 opaque reddish-brown, more blaekish at the base. Abdomen : first segment grey ; second segment 

 yellow, with a large y-shaped opaque black marking, the stem broad, and extending laterally to the 

 margin posteriorly as a narrow brownish baud ; third segment with a median opaque black stripe and a 

 narrow brown. or blackish posterior band : fourth segment reddish or brown,w r ith a narrow shining cross- 

 band ; second, third, and fourth segments eaeh with a narrow light yellow hind margin ; hypopygium 

 shining black. Legs : feinora, except tbe tip, tip of four anterior tarsi, and the hind tarsi, black : 

 elsewhere red ; hind femora thickeued. Wings hyaline, sometimes tinged with yeUow on the basal 

 anterior part. 



Female. Eront narrowed above, with an opaque black band below tbe ocelli and black pile. Abdomen shiuiug 

 black; seeoud, third, and fourth segments each with a narrow yellow hind margin and a posterior opaque 

 black band; second segment with an anterior band, connected broadly in the middle with the posterior 

 one, the third segment with an anterior oval spot, and the fourth and fifth segments each with an 

 anterior, narrow band, opaque black. 



Length 9-1 L millini. 



Hab. Mexico, Xucumanatlan 7000 feet, Omilteme 8000 feet, both in Guerrero 

 (//. H. Smith). 



Four specimens. 



9. Eristalis cosmius. 



Eristalis cosmius, Schiner, Reise der Novara, Diptera, p. 362 K 

 Hab. Mexico, Jalapa (M. Trujillo).—SomK America 1 . 



A single male specimen from Jalapa seems to belong to this species. It differs from 

 the description in the tip of the scutellum being shining, not 44 schiefergrau," in the 

 abdomen being distinctly pilose, in the red spots of the fourth segment being very 

 small, and in the femora being black, not " pechschwarz." 



10. Eristalis furcatus. 



Eristalis furcatus, Wiedem. Zool. Mag. Kiel, i. 3, p. 51 1 ; Aussereur. zweifl. Ins. ii. p. 176 2 ; 



Schiner, Keise der Novara, Diptera, p. 36.2 3 ; v. d. Wulp, Tijdsclir. v. Ent. xxv. p. 131 4 ; 



Willist. Trans. Am. Ent. Soc. xv. p. 279 \ 

 Eristalis femoratus, Macq. Dipt. Exot. ii. 2, p. 40, t. 9. f. 6 a . 



