612 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXV. 



Suborder II.— ZYCIOPTERA. 



Both pairs of wings identical in shape or at least nearly so. No forma- 

 tion of trigone or hypertrigone bnt in place of these, in the same area, an 

 entire or traversed, right-angled or irregular rhomboid. Between the 7th 

 and 8th nervures no differentiated discoidal field. Ej'^es clubbed, laterally 

 prominent, separated, the space between them much broader than the 

 breadth of one eye as seen from above. No vesicle present ; the ocelli 

 lying free in the middle of the forehead. The middle lobe and the two 

 labial palps approximately the same size, the middle lobe deeply fissured. 

 Male with pairs of superior anal appendages at the end of the 10th abdomi- 

 nal segment and pairs of inferior anal appendages at sides of anal orifice. 

 The female with an ovipositor very similar to that of the Aeschnince, only 

 more developed. 



[Wings of the imago held closed together over the dorsum when 

 at rest.] 



Larva : o-tailed, foliate or stillette-shaped tracheal organs, the mid- 

 dorsal out of the nth tergit, the latero-ventral out of the 11th 

 sternit. 



Key to FAMiiiEis. 



Node of wing remote from base. 



Numerous antenodal nervures between costa and sub- 

 costa. 



A general tendency to very close reticulation. 



Often with partially metallic-coloured wings . . . . C'cdopterygidce. 



Node of wing close to base. 



Only two antenodal nervures. 



A tendency to the reduction of reticulation of wings. 



Only minor secondary nervures. 



Only very occasionally with coloured wings . . . . Af/riomdcs. 



Suborder 1.— ANISOPTERA. 



Family I. — Liuellulid.e. 

 S ubf amily I . — Libellulince. 



The Libellulime are represented in India by species belonging to 34 

 different genera and form by far the largest subfauuly of Dragonflies, 



Although possessing a characteristic facies, considerable differentiation 

 is found in shape, size and colour, and more especially in the morphology 

 of the sexual organs of the males. They have a fairly general distribution, 

 being found in the wet and dry zones, in the temperate, subtropical and 

 tropical. 



Generally they are insects of medium size with a robust thorax and a 

 stout abdomen which latter part however is extremely variable and may 

 be long and slender, short and depressed or compressed, cylindrical, 

 parallel-sided, fusiform or a combination of any of these shapes. 



They may be recognised by the following characters: — • 



1 . Eyes always to a greater or lesser extent contiguous. 



2. Occiput always triangular in shape. 



o. The ocelli always arranged in a triangle around the vesicle. 



4. The mid-lobe of the labium much smaller than the lateral, the 



terminal segment of the latter being missing, 

 o. The base of the hind-wing straight or rounded, never indented. 



