Page:Jardine Naturalist's library Entomology.djvu/296

290 in most cases, are short and slender, the tarsi varying in the number of joints from three (their amount in dragon flies,) to five (as among the Hemerobii, &c.) The transformations of this order differ in their nature in different tribes, some undergoing a semi-metamorphosis, others a complete one. The larvæ are constantly provided with six feet, and many of them reside in the water. The majority of the larvæ, as well as of the perfect insects, are carnivorous; a few are omnivorous in all their states. We have upwards of 200 Neuropterous species in Britain, and of these certain of the Libellulæ are among the largest insects found in this country. Latreille divides this order into two primary groups, discriminated by the shape of the antennæ:—, having these organs minute and setiform, with not more than seven joints;, having long antennæ, composed of numerous joints, and for the most part filiform. The former section comprehends the families Libellulidæ (Dragon-flies,) and Ephemeridæ (May-flies;) the latter contains the Panorpidæ, (Scorpion-flies,) Myrmeleonidæ, (Ant-lions,) Hemerobiidæ, (Day-flies,) Termitidæ, (White-ants,) Raphidiidæ, Psocidæ, Perlidæ. The dragon-flies are well known insects, owing to their large size, frequent occurrence, and their beautiful and varied colouring. Such of them as are now referred to the old genus Libellula, may be recognised by having their wings extended horizontally during repose; a vesicular elevation on the