60 INSECTA. 
Fabricius, anticipated in this* pointy by eaaiour; divides the 
Libellule into three genera. 23 Ahn dog 
. 
LIBELLULA, Fab. 
Or Libellula proper, where the wings are extended horizontally 
when at rest. The head is almost globular, with.very large, conti- 
guous or closely approximated eyes, and a vesicular elevation on the 
vertex, with an ocellus on each side; the other or anterior ocellus 
is much larger. The middle division of the labium is much 
smaller than the lateral ones(1), which unite beneath by a longitudi- 
nal suture, and close the mouth exactly. The abdomen is ensiform 
and flattened. 
The larve and.the nymphs have five appendages at the posterior 
extremity of. the body, forming a pointed tail; their body is short, 
the mentonniére convex, in the form of a helmet, with the two pin- 
cers resembling shutters. . es 
L. depressa; L.; Rees., Insect. Aquat. VI, vii, 3. Brown 
somewhat yellongins base of the wings blackish; two yellow 
lines on the thorax; abdomen ensiform, sometimes brown, and 
at others slate coloured, with yellowish sides(2). 
sana; Fab. 3 . 
The shnz resemble the Libellulz proper in their mode of bear- 
ing their wings, and in the form of their head, but their two poste- 
rior ocelli are placed on a simple transverse elevation in the form 
of acarina. The intermediate lobe of the labium is also larger, . 
and the two others are distant and armed with a very stout tooth 
and spiniform appendage. The abdomen is always narrow a elon- 
‘gated. . , 
The body of the larve and the nymphs is also'more etbiWated in 
that of the Libellulz in the same states. The mask is flat, and the two. 
pincers are narrow, and have ‘a small movable nail at the extremity. 
: 
(1) These lateral divisions or palpi present a remarkable differenges in the three 
subgenera. 
(2) For the other species, see Fabricius, ein Syst., and Latreille, Hist. 
Gener. des Crust. et des Insect., XII, p. 10, et seq:; but particularly the Mono- 
graphs of the Insects of this family, from the environs of Bologne, published in 
Latin by M. Van der Linden, that which he has since given on the species of 
Europe, and finally another Monograph of European Libellule, forming a part of 
the already quoted work of M. Toussaint ida aieingeat : 
