364 ■ Syrphidae. 



nounced, broadly rounded. Alula very narrow, almost wanting. Squa- 

 mulæ very narrow, especially the thoracai squamula; alar squamula 

 with short, simple hairs, thoracai squamula with not dense hairs, 

 partly simple, partly somewhat branched, especially towards the angulus. 

 Plumula very short, almost rudimentary, with the hairs partly simple, 

 partly branched from the base. 



The developmental stages of B. cochenillivora from Guatemala are 

 mentioned by Guérin-Méneville (Ann. Soc. Ent. de Fr. 2, VI, 1848, 

 Bull. 79 and Revue Zool. XI, 1848, 350): the larva feeds on cochineal 

 and is destructive to them. The larva of B. elongata (fabida) has 

 been described by Snelien v. Vollenhoven (Handl. d. Nederl, Ent. Ver. 

 1854), but I have not seen this paper. The larva is said to be similar 

 to a Syrphus-larva, and to be aphidiphagous. Osten Sacken has 

 recorded (Stett. Ent. Zeitg. 1862, 412) the facts then known about the 

 Baccha-\3i\'Vdi, and he mentions here a Baccha from the southern 

 United States, feeding on Coccus infesting orange-trees. B. elongata is 

 mentioned as bred by Bradley (Entom. Month. Mag. XXXII, 1896, 256); 

 in the case, in which the pupa was, a larva of Mamestra persicaria 

 had been, and it was suggested, that the Baccha was possibly bred 

 from it. Morley mentions (Ent. Month. Mag. XLVI, 1910, 192) B. obscuri- 

 pemiis depositing eggs between Aphides (^4. pruni) on the leaf of a 

 buUace in the beginning of July. I have myself examined a pupa of 

 B. ohscuripennis?, taken as larva in flood refuse in a fen on ^^4, it 

 pupated ^"/4 and developed on ^^/s. The pupa is of a rather curious 

 shape; it is elongate, the anterior part high and rounded and curved 

 somewhat downwards, the rest low; along the middle this low part 

 is a little arched, but along each side is an impressed line or long- 

 itudinal furrow, the side margins being again a little raised ; above at 

 the apex is a short spiracular process, directed upwards and a little 

 divided at the end; the pupa is attached by its posterior part and is 

 here flat; it is yellowish brown with some darker brown markings on 

 the anterior part. The length is nearly 7 mm. To judge from the 

 time on which the larva was found it hibernates. 



The species of Baccha are very characteristic flies by their long 

 and slender shape; they occur in woods and thickets, on shaded and 

 more or less humid piaces and are here seen hovering; they are in- 

 defatigable hoverers and their flight is a nice view, especially the male 

 of B. obsciiripennis with its dark wings forms a pretty sight: they are 

 also seen resting on piants. 



Of the genus 4 species are recorded from the palæarctic region, 

 but only 2 are European (see below under the remarks after the 

 species), both also occurring in Denmark. 



