Xanthogramma. 355 



descending; the oral aperture large but not long. Mouth parts chiefly 

 as in Sphaerophoria, but relatively shorter and stouter, labrum and 

 hypopharynx considerably shorter; palpi short. Thorax rectangular, 

 with a yellow stripe at the side margin, and with one or more yellow 

 spots on pleura; metapleura with quite short, dense hairs. Seutellum 

 yellow with the basal part darkened or black; is has no marginal 

 fringe below. Abdomen ovate, a little restricted towards the base; it 

 is distinctly marginate; in the male there are five not transformed 

 segments both on dorsal and ventral side, the fifth not quite small, 

 larger than in Syrphus (and hence with distinct yellow markings). 

 Genitalia small, of usual shape. In Ihe female abdomen has likewise 

 five distinctly visible segments, but generally one to three more, but 

 small, are seen. Legs simple and quite short-haired, also the hairs 

 behind anterior femora rather short, and hind femora not at all with 

 longer hairs. Wings with the medial cross-vein well before the middle 

 of the diseal cell; cubital vein with a distinct, though slight curve 

 about the middle; the basal part of the radial vein to the base of 

 the cubital vein with very fine, bristly hairs; vena spuria not strong. 

 Alula large. Squamulæ blackish, still narrower than in Sphaerophoria, 

 especially the thoracai squamula; alar squamula with short, simple 

 hairs, thoracai squamula with somewhat long, branched hairs. Plumula 

 somewhat thin and delicate, with not dense, plumose hairs (Girschner 

 says "einfachen oder nur undeutlich gegabelten Hårchen", I find them 

 distinctly plumose). 



The developmental stages of X or-natum are mentioned by BeUng 

 (Arch. fiir Naturg. 48, 2, 1882, 232, 38). The author found some larvæ 

 in the ground under turf (in einem beraseten Erdhaufen) on ^'^k ; in 

 the same place he took larvæ the foUowing year on "^^Vi ; they pupated 

 towards the end of May, and the imagines came on ^^/e — '^^le. The 

 folio wing year larvæ were again taken in the same place on ^^/2, they 

 pupated on "^1/5, but gave only parasitical Hymenoptera. Two larvæ 

 taken in the ground on a meadow on ^^/s pupated on Ve and developed 

 on '^^/e— ^/7. I have myself had the larva of X. ornatitm, it was taken by 

 Mr. Kryger, who found it sitting on an Ononis procurrens, in September; 

 it hibernated quite motionless, and next spring on ^^/s it contracted and 

 took the pupal shape, and on ^^k it was a pupa; the imago came on 

 ^^/i; further I possess a specimen oi X. citrofasciatum bred from a 

 pupa found under a stone on ^''/4 and developing in May. — The 

 larva of ornatum is described as somewhat flat below, arched above 

 with a shallow, longitudinal furrow; the body divided into 30 — -36 

 corrugations ; the second, third and fourth corrugations each with a 

 transverse rpw of distinct, brown tubercles ending in a short hair. 



23* 



