DIPTERA. — TABANID@®. 541 
I think with the Chameleon itself that 
“ You both are right, and both are wrong.” 
It has long been noticed that (as in the Culicide) it is only the 
females of these insects which are blood-suckers, the males being 
found on flowers ; and Meigen discovered that the mouth of the latter 
sex is destitute of mandibles. The same remark has also been made 
by Curtis in Heematopota*, whence he is induced to believe that it is 
the mandibles which are the real piercing instruments, and that the 
other enclosed lancet-like pieces form a canal for the upward passage 
of the blood. M. Westermann observed of Pangonia rostrata (Sil- 
berm. Fev. Ent. No. 3.), that its bite is very powerful, but it is only 
able to inflict a wound upon cattle whilst on the wing, owing to the 
very great length of its proboscisf; it seems, however, to prefer the 
flowers of Pelargonium, upon which it is often found. M. Serville, 
however (Ann. Soc. Ent. France, tom. ii. p. 493.), suggests that it is 
only the males which are found in the latter situation from analogy 
with the Tabani. 
We are indebted to De Geer for the knowledge we possess of 
the transformations of this family. The larva (fig. 128. 9.) of Ta- 
banus bovinus De Geer (Mém. tom. vi. pl. 12. f.6.) is found in the 
earth, and is of an elongated subcylindric form, attenuated at each 
end, especially in front; it is destitute of feet, 12-jointed, having 
the head distinct, narrow, elongated, horny, armed with two strong 
curved hooks, antenne and palpi; the fourth to the tenth segments 
having an elevated dorsal papillose ridge used in progression; the 
terminal segment is minute and tuberculiform ; the pupa is naked, in- 
complete, elongated, subcylindrical, with six spines at the end of the 
body (fig. 128.10.) ; the margins of the abdominal segments ciliated, 
and the forehead bi-tubercled. 
* He is silent as to the composition of the mouth of the male of Tabanus. 
+ In the species of Pangonia observed by Meigen (vol. ii. tab. 13. fig. 3, 4.), the 
proboscis is not more than half the length of the body, and the enclosed lancets are 
as long as the labium; but in P. longirostris Hardw., which I have dissected, and 
in which the rostrum is nearly three times the length of the body, the six enclosed 
lancets are not half the length of the labium. I consequently do not think that the 
insect can use these lancets, except by detaching them from the labium, and holding 
the latter at a great angle from the other parts of the mouth. 
