OCR Text |
Show 282 INSECTA• CERATOPHYA, Wied. . . t of the antenn~ nearly twice the Scutellum unarmed; third JOin length of the first( 1 ). L t -Mulio Fab.-.Microdon, Meig. APHRITrs, a · ' 11 m presents t wo teeth.' the first joint of thh e an- Where the scute u o following ones taken toget er. tenn~ is almost as long as ~he t:b enus, as in Ascia, the two first In this and the prec~dmg g min a ted in the manner of an closed cells of the postenor edge are ter angle(2). . S r hid~ are shorter than the head. The antenn~ of the following y p ·f cularly in one of the sexes. The posterior legs are often large, pat. 1 blong and almost in the 11 t f the antenn~ 1s 0 d Sometimes the pa e . o The osterior thighs are thick an form of an elonga:ed trlan.gle. bent pone on the other. dentated. The wmgs are meum ' MEnonoN, l\•tJr. e•i g. F a b •- Milesia, Eristalis, Lat.-Syrphus, Fab. . . lar or conical, without being nar- Where the abdomen 1S tr1angu 1 11 f the posterior edge of d at base and where the externa ce o rowe ' · d xteriorly the wings is deeply emargmate ~ . b ··Reaum Insect. IV,xxx. M. narcissi; Eristalis narc,ss~,.Fa ., ., . 1 s black; Obscure-b ronze, but covered Wlth fulvous down, eg . f t · · legs tubercu1 o us. . inner s1de o the pos erlOr . . f he bulb of the N arctss· The larva feeds on the mterlOr o t us(3). AsoiA, Meg. Meig. Where the abdomen is narrowed at b ase a nd. clavteartem. inaTteh ein t waon first closed cells of the posterior ed.ge of ~he wmgs angle; the exterior side of the first 15 straight( 4 ). (1) Wied., Anal., Entom., fig. 9. . d Fallen (2) See Lat.' Gener. Crust. et Insect., IV, 329, MeJg. an . (3) See Meigen. (4) Idem. DIPTERA. 283 Sometimes the palette of the antennre is short, or moderately elongated, and either almost orbicular or nearly ovoid. Here, as in the last subgenus, the abdomen is narrowed at base and clavate. SPHEGINA, Meig. Where the palette of the antennre is orbicular. The posterior thighs are clavate and spinous underneath( 1 ). There, the abdomen is either triangular or conical, or almost cylindrical. In some, the wings hardly extend beyond the abdomen, which is frequently narl'ow and elongated. We will separate those whose posterior thighs are strongly inflated, with the inner side armed with small spines. The closed cells of the posterior border of the wings are sinuous posteriorly. Eu:MERus, Meig. To which we unite his Zylotag, where the abdomen is merely narrower and almost linear, and which we formerly placed among the Milesire. Such is the E. pipiens; Musca pipiens, L.; Panz.; Faun. Insect. Germ. XXXII, 20. About four lines in length; black; each side of the abdomen spotted with white. The humming it produces while on the wing is mingled with a sharp sound resembling the note of a young chicken(2). In the two following subgenera, the posterior thighs sometimes differ but little from those of the preceding ones, and are sometimes thicker, but unidentated at most. MrLESIA, Lat. Fab. Meig.-Tropidia, Meig. Where the two posterior legs are abruptly iarger than the others, with thick and unidentated thighs in several. The body is elongated, and the abdomen conical, or almost cylindrical and convex( 3). (1) Idem. (2) See Meigen, genera Eumerua and Xylota. (3) Idem, genera Myle~ia, Tropidia. The palette of the antenme of the Tropid. ia: is proportionally wider, and as if truncated or very obtuie. |