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her embryo burden to that element from which she herself once emerged, though 
its chill embrace would now involve her in destruction. Yet how fearlessly, how 
easily she accomplishes what might have been considered a difficult task ; not tim¬ 
orously clinging to a rush to perform the process, but circumvolitating the pool, 
depositing her eggs in the progress, and thus giving her offspring ample room and 
verge enough in the depths below for their future operations. And this bears the 
unmeaning name of instinct. But is not the Libellula while thus making provi¬ 
sion for her offspring in an element where she herself would now perish, sensible 
that she formerly emerged from the water, and that her offspring must there for 
their allotted time undergo the same processes of development which she passed 
through, prior to being fitted to sport in air and perform the economy of her ma¬ 
ture state ? At all events the contemplation of an incident like this is not without 
a note of instruction in the wide extended field of natural theology. 
The beautiful and elegant tribe of Libellulidce were all included by Linneus 
in one genus, and, as remarked by Stephens, the Linnean character of one species 
is so comprehensive that it positively embraces no less than two genera (Lestes , 
Leach, and Agrion , Fab.), one containing three, and the other ten, indigenous 
species in its extensive grasp! and the consequence has been that Latreille and 
other celebrated entomologists assert that the sexes unite pell-mell together, and 
that the varieties resulting therefrom are innumerable; whereas, the fact is that 
these insects are as particular in their amours as any others, and the varieties are 
equally referrible to their proper species, the male usually, however, differing from 
the female in colour. This last circumstance has caused some confusion in the 
naming of species ; and to be accurate in the study of this tribe it is indispensable 
to observe them when in union. Fabricius subdivided the Libellulidce into three 
genera, Libellula , AEshna, and Agrion , which have been generally retained by 
entomologists, though much extended by Dr. Leach. I shall, however, here ad¬ 
here to the Fabrician arrangement, as sufficient for the present occasion, and 
perhaps a British example under each may be useful to the young inquirer. All 
the species of this tribe have two great lateral eyes, and three smaller ones or 
ocelli, situated on the vertex, antennae minute and almost concealed, strong cor¬ 
neous mandibles, wings extended horizontally or meeting vertically above the 
back, reticulated in an admirably delicate manner, and with the tarsi three- 
jointed. The larvae and chrysalides inhabit the water till the period of their ulti¬ 
mate metamorphosis, and bear a considerable resemblance in form to the perfect 
insect, but having only the rudiments of wings. They are remarkable for the sin¬ 
gular construction of the piece which replaces the lower lip, covering the mandi¬ 
bles, maxillae, and almost the whole under part of the head ; it has been compared 
to, and called by some, a mask. Having completed the initiatory period of their 
existence, the pupae issue from the water, climb up the stems of reeds and other 
aquatic plants, and, divesting themselves of their old skins, prepare for the enjoy- 
