BACCHA. 



39 



One male and tvvo females. 



I describe the male and female speciraens above as belonging to one species, but it is 

 possible that they are distinct. In addition to the differences noted in the wings and 

 hind tarsi, the female has the abdomen distinctly more slender basally, while the reverse 

 shouid be the case ; the abdomen in the female distally is covered with sparse recumbent 

 short white hairs, while the covering of the male is black pile. The male also has the 

 wings more yellowish. 



The male differs from the same sex of B. coerulea chiefly in the eye-facets above not 

 being enlarged, in the more spatulate abdomen, without the white hairs, in the absence 

 of the clouds at the ends of the marginal and submarginal cells, and in the colour of 

 the hind tarsi. The female is best distinguished by the very narrow front above. 



18. Baccha luctuosa. 



Baccha luctuosa, Bigot, Ann. Soc. Ent. Fr. 1883, p. 334 \ 

 Hab. Mexico l . 



It is possible that a female specimen from Cache, Costa Kica (Bogers), may be of 

 the same species as the male described by Bigot from Mexico. I therefore give a 

 description of it : — 



Front much narrowed above ; black, on the sides below red ; pile black. Antennje red ; third joint orbicwlar, 

 brownish above. Pace yellow. Mesonotum blackish-brown, with marked purplo and bronze reflections, 

 the lateral margins yellow. Pleura? shining blue, largely yellow in front. Scutellum subtranslucent 

 reddish-yellow. Abdomen deep blackish-brown, with marked purple reflections, only a little narrowed at 

 the base ; Qrst segment yellow on the sides ; second segment with a narrow band ; third segment with a 

 pair of small yellow triangles ; fourth segment with a pair of yellow V-shaped spots, the angles of which 

 are obtuse and the inner subparallel rami longer than the outer ones ; fifth segment with two yellow 

 stripes. Legs and coxae light yellow ; hind femora and tibiae, save the knees, brown. Wings uniformly 

 deep yellowish-brown ; aluke rudimentary. 



Length 9 millim. 



The ocelli are remote from the vertex, as in the genus Mesogramma, and the 

 species otherwise is a rather aberrant Baceha. 



The following species have also been recorded from within our limits : — 



Baccha lineata, Macq. Dipt. Exot. l er Suppl. p. 139, t. 20. f. 5.— Texas or 

 Yucatan. 



marmorata, Bigot, Ann. Soc. Ent. Fr. 1883, p. 333. — Mexico. 



B. lineata may be synonymous with B. livida, Schiner. 



