32 DIPTERA. 
1. Echinomyia robusta. (Tab. II. fig. 10a, head in profile.) 
Tachina robusta, Wiedem. Aussereur. zweifl. Ins. ii. p. 290. 15°. 
Echinomyia robusta, van der Wulp, Tijdschr. voor Ent. xxvi. p. 19. 8°. 
Echinomyia analis, Macq. Dipt. Exot., Suppl. i. p. 144. 4, t. 12. f 3. 
Echinomyia filipalpis, Rond. Arch. per la Zool. iii. (sep. p. 15). 
Echinomyia hemorrhoa, van der Wulp, Tijdschr. voor Ent. x. p. 145, t. 4. ff. 18-16°; Williston, 
Trans. Am. Ent. Soc. xiii. p. 301+. 
Hab. Norta America, Wisconsin ?, White Mountains 4-—Mexico, Ciudad in Durango 
8100 feet (Forrer) ; Cosra Rica, Volcan de Irazu 6000 to 7000 feet (Rogers).—CoLomBIa ; 
Cuit1; Urvavay, Monte Video!; ARGENTINE REPUBLIC 2. 
Several specimens of both sexes. This species varies considerably in the more or 
less extension of the rufous portions on the abdomen. This colour generally predomi- 
nates in the male specimens, frequently so much so that there remains only a black 
dorsal band; on the contrary in the females the abdomen is sometimes wholly black, 
except the fourth segment (hemorrhoa, v. d. Wulp). However, there occur also males 
with very little, and females with very much red coloration on the abdomen. On 
account of this diversity, I believe that all the above-cited descriptions refer to one and 
the same species, which seems to be common almost everywhere in North and South 
America. 
Perhaps Echinomyia filipalpis, Thoms. (Dipt. Eugen. Resa, p. 517), may also be 
regarded as synonymous with E. robusta. . The principal difference seems to exist in 
the dark colour of the first antennal joint, and in the tibie, the middle portion of the. 
latter being rufous, characters which I do not observe in any of my specimens. 
Williston 4 considers it as a distinct species, of which he possesses both sexes; he gives 
it the new name of E. thomsoni, in order to avoid conflict with EL. filipalpis, Rond. 
As synonymous with my EL. hemorrhoa, Williston cites, with doubt, Tachina anaxias, 
Walk. (List Dipt. Brit. Mus. iv. p. 726); though this description may agree tolerably 
with my insect, I find, however, a serious difficulty in Walker’s expression, “no bristles 
on the side of the face,” which is opposed to the fact that genal bristles are present in 
E. robusta, Wiedem., and also in my £. hemorrhoa. 
2. Echinomyia flaviventris, sp.n. ¢ @. (Tab. II. figg. 11; lla, head in 
profile.) 
Thorax cinereous; scutellum testaceous; abdomen yellow, with the fourth segment black; head whitish, with 
two genal bristles; antenne black, in the middle part rufous; palpi filiform, pale rufous; legs black, with 
reddish tibiz ; wings grey, with a yellowish base. 
Length 13-16 millim. 
Head at least as broad as the thorax, sericeous yellowish-white; cheeks with a long weak blackish pile and 
two bristles; front cinereous, with a dark rufous, more or less divided, median band; frontal bristles 
strong, descending to the number of three or four in a curved row beneath the root of the antenne ; 
vibrisse accompanied above by two and below by a row of shorter bristles; beard and pilosity of the 
occiput yellowish-white. Antenne black; the second joint at the end and the third joint at its base 
