90 NEUROPTEKA. 



eyes are hardly contiguous ; but they are completely so in the 

 JSaekmuuB. These sub-families include the largest of the British 

 dragon-flies, several of which are very common. Their bodies, 

 however, though longer, are not so stout in proportion as in the 

 Libellulince. jtEschna Grandis, Linn., is a reddish-brown insect, more 

 than two and a half inches in length, and sometimes nearly four 

 inches in expanse ; the wings are of a smoky yellow. M. Cyanea, 

 Miill., and several allied species, are brown or reddish, tessel- 

 lated with blue, brown, or yellow ; the wings are hyaline. Cordu- 

 legaster Annulatus, Latr., is a magnificent species of equal size, but 

 belonging to the Gomphince ; it is black, the thorax striped, and 

 the abdomen banded with yellow. All these species are very 

 strong on the wing. 



FAMILY II. Agrionidce. 



Eyes widely apart ; fore and hind wings of equal width ; bodies 

 long, slender, and weak. 



This family is divided into two sub-families, the Calepterygma, 

 which includes large species, with numerous short transverse ner- 

 vures on the front edge of the wings ; and the Agrionince, which 

 are more delicate insects, with only two such nervures. The 

 Calepterygince are also often distinguished by the beautiful colours 

 of their wings, a character which does not occur to the same extent 

 in other dragon-flies We have two species of Calepteryx in England, 

 which have a low and rather heavy flapping flight over the water 

 of small streams. They are very conspicuous insects of a metallic 

 blue colour ; the males of C. Virgo, Linn., have deep blue wings, 

 those of the female being greenish or brown ; and G. Splendens, 

 Harr., has transparent wings, with a deep blue band across the 

 middle of each in the male. One of the most beautiful of the 

 foreign species is C. Chinensis, Linn., a common East Indian species, 

 in which the fore wings are transparent, and the hind wings are 

 of a brilliant green, in the male. The American genus Hetcerina, 

 Hag., is allied to Calepteryx, but the wings are narrower, and 

 transparent, with a blood-red space at the base of each. 



The principal genera of the Agrionince are easily distinguished 

 by the shape of the stigma (or pterostigma), a small opaque spot 

 on the costa towards the tip of the wings. Most of the species of 

 Lestes, Leach, are bright metallic green, and the stigma is large 

 and oblong; they expand about an inch and a half across the 

 wings. In Agrion, Fabr., the stigma is small and lozenge-shaped, 



