204 
BRITISH BEETLES. 
The Sagrina (which comprise some very large and 
splendid exotic insects) are here only represented by 
a single genus, Omodacna ; the few British species 
of which are of considerable rarity, being usually found 
in the blossoms of the white-thorn. They are small, 
narrow, linear insects, exhibiting no particular points 
for observation. 
In this family the apex of the mandibles is entire, 
without emargination ; and the labium is deeply in- 
cised, so as to become bilobed. 
The Donaciina have the antenme long, and inserted 
before the eyes ; the head prominent, and rather 
constricted behind ; the first segment of the abdomen 
as long as all the rest together ; and the legs long 
and straggling, the femora (and especially the hinder 
pair) being often much thickened and toothed on the 
under side. 
We possess two genera, Donacia and Hxmonia ; 
the members of which are exclusively attached to 
water-plants (as the specific names of many of them 
import), in the stems of which their naked larvaj are 
found ; the pupae being enclosed in transparent 
silken cocoons, attached to the roots or filaments. The 
Donacia: are all more or less coarsely punctured and 
metallic above, with fine silky down on the under- 
side ; they have a narrow thorax and somewhat flat- 
tened elytra, and are usually found in great numbers, 
being gregarious. Some of the species have a varie- 
gated longitudinal metallic stripe on each wing-case ; 
“ Sagridce, Donaciadce,” &c. ; the members of the whole group 
Cfirysomelidce are, however, so closely connected that they can- 
not with reason be regarded as more than tribes at the most. 
Ed. 
