part it.] THE INSECTS WHICH VISIT FLOWERS. 43 
blood-sucking, the other honey-sucking; while the males are all 
alike and all feed on honey. 
In the Conopide, the proboscis, which is still carried downwards, 
is bent, when of considerable length, at the base, and sometimes 
again near the middle; and then, in the latter case, the anterior 
part shuts up into the posterior like the blade into the handle 
of a pocket-knife, so that the proboscis may still be carried in 
a vertical position. 
The species of Bombylius, on the other bacid: carry their proboscis 
(which is likewise too long to be carried downwards and unbent) 
directed straight forwards, and permanently ready for action. They 
Fia. 8. —Conopide and Bombyliide (Bee-flies). 
1.—A Conopid, Licus ferrugineus (x 1°7). 
2.—Head of ditto, with extended proboscis. 
3.—Proboscis folded like the blade in a pocket-knife. 
4.—A Bombylid, Bombylius major (x 1°7). 
5.—Its proboscis, more highly magnified. 
thus save time, sucking as they hover in the air over each flower with- 
out settling, and flying rapidly from one to another. In the length 
of their proboscis they approach Rhingia, Bombylius major having 
a proboscis 10 mm. long, and B. discolor one of 11 to 12 mm.; they 
also nearly rival Rhingia in their powers of detecting concealed 
honey. The species of Bombylius, like those of Hmpis, are fitted 
also for boring into succulent tissues. For the labium and the 
labrum inclosed by it form two grooves uniting into a tube in 
which the maxillz, as two very fine bristles, and the mandibles, 
united into one broad, strong, pointed bristle, move backwards and 
1 Fritz Miiller, Kosmos, vol. viii. pp. 37-42. 
