570 Syrphidae. 



stripe and the black part below, Jowls pale reddish yellow. Occiput 

 whitish grev pruinose, the hairs somewhat long, whitish below, yellow 

 above, and here with a row of black hairs overhanging the eyes. 

 Eyes with short, whitish hairs. Antennæ black, third joint not so 



Fig. 192. Antenua of C. cautum d", from the inside, x 40. 



long as the two basal joints together, of which latter the first (on 

 the inside) is a little more than half as long as the second; arista 

 about of the length of the third joint, yellow in the basal half, black 

 on the apex. Thorax black, shining, with two abbreviated, greyish 

 middle stripes, diverging behind and merging into a faint greyish space 

 in front of scutellum; at the sides there is a yellow spot from the 

 humeri to the transverse furrow and one on the postalar callus, pro- 

 longed somewhat forwards; thorax is clothed with somewhat long, 

 brownish yellow hairs, darker across the middle; they are longest 

 behind ; above the wing-root are dense black hairs. Scutellum brownish 

 or blackish above with a yellow margin ; seen from the side it is more 

 yellow; it has long, black hairs, yellow on the base. Pleura with a 

 yellow or reddish spot down on mesopleura, a more or less faint 

 spot above on sternopleura and the metapleura yellow; they have 

 long, yellow hairs, somewhat tuft-like above. Abdomen black, duUish, 

 slightly shining at the hind margins of the segments; the fifth segment 

 has the hind part bent somewhat upwards on account of the large 

 genitalia; abdomen has four somewhat bow-shaped, yellow bands, 

 interrupted in the middle, and the hind margins of the segments are 

 yellow; the middle interruptions of the bands decrease in breadth 

 backwards; the bands are widened at the sides, they do not reach 

 the side margin but so do the yellow hind margins, and the bands 

 are connected with the hind margins at the posterior corners ; the hind 

 margins increase in breadth backwards, on the second segment the 

 margin is narrow, often present only at the sides, and on the fifth 



