74 BOMBYLID.E. 



closely approximate at the base, diverging towards the tips ; first and 

 second joints bristly ; first cylindrical, moderately long ; second cya- 

 thiform, very short ; third conical, bare, somewhat longer than the first ; 

 fourth and fifth extremely small. Thorax oval, hairy, with bristles 

 intermixed, generally with 3 darker stripes ; no transverse suture ; 

 scutellum semicircular. Wings lanceolate, of moderate length, half- 

 deflexed, very finely pubescent ; longitudinal veins almost straight. 

 Alula) entire, very small. Halteres uncovered. Abdomen obconical, 

 finely pubescent. Legs bristly, rather slender ; tips of the tibia? armed 

 with spines. 



Male. Head almost semicircular. Eyes contiguous. 



Fern. Head spheroidal. Eyes more or less parted. 



The Thereva often settle on the ground in sandy spots, and in- 

 habit the leaves of shrubs, the trunks of trees, and flowers ; and 

 sometimes prey on other insects. They are not rare, but never 

 very numerous; their flight is sudden, short, and very swift; 

 the males also sometimes dance together in the air. The larvae 

 are vermiform, with twenty segments, and live in the earth. The 

 pupae are bare, pale, nearly cylindrical, with many segments, hardly 

 furnished with bristles, armed in front with 2 subulate little horns, 

 and have been found under stones in sandy plains. The sexes 

 differ in the colour of the pubescence. 



1. bipunctata, Mg. zw. ii. 121. 9 (1820) ; Ztt. ; Lw. Mas. Nigri- 

 canSijlavido-cinereo-tomentosa., abdominis segmentis secundo et sequentibus 

 flavo-marginatis obscure flavido-cinereo-fasciatis, fasciis latis non bene 

 determinatis, alis hyalinis stigmate fusco. Fcem. Cinerascens, frontis 

 maculis duabus nigris nitidis, thoracis vittis tribus dorsalibus fusco-cine- 

 reis, abdominis segmentis cinereo-fasciatis, apicem versus pilis pallidis mi- 

 nutis. Long. 4-4 ; alar. 7-8 lin. 



Black. Body with a tawny covering, thickly clothed with tawny hairs. 

 Head with a few black hairs behind the eyes and on the crown. First 

 and second joints of the antennae clothed with tawny hairs, beset with 

 black bristles. Thorax hoary beneath. Wings pale grey, tinged with 

 brown at the base, and beneath the fore border, and along the borders 

 of the veins ; veins black, tawny towards the base and along the hind 

 border. Halteres tawny. Abdomen cinereous beneath. Legs beset 

 with black bristles ; femora clothed with tawny hairs ; tibiae tawny, 

 with black tips ; first and second joints of the hind tarsi tawny, with 

 black tips ; third joint of the hind tarsi and first joint of the anterior 

 tarsi tawny at the base. Male. Epistoma with a few black hairs on 

 each side. Halteres with black knobs. Abdomen gilded on the Jdnd 

 borders of the segments ; a few black hairs at the tip. Fern. Head 

 clothed with yellow hairs, whitish beneath ; 2 black shining united spots 

 on the crown. Thorax with two pale tawny stripes. Wings a little 



