26 NOTES ON 
antenne are straight and stiff, and the eyes are 
much smaller in proportion to the size of the 
head than at a later period of its existence. As it 
increases in magnitude, the wings are gradually 
developed, and it is then termed the pupa. In 
proportion as it approaches its transmutation 
into the perfect fly, it becomes sluggish in its 
motions, and often remains stationary on the 
stalks of plants, with its head directed down- 
wards, eluding observation, from its colour ap- 
proximating to that of the plant on which it 
rests. At this period it evinces much cunning 
in the gratification of its predaceous appetite, 
which ceases a short time previous to its change. 
During its growth it casts its skin several 
times. These exuvie are beautiful objects for 
the microscope, as they are quite transparent, 
and exhibit the prominences, depressions, and 
markings of every member, being, in fact, a 
perfect mould of the creature. 
The magnified representation of this Libellula, 
given in plate 3, was taken just before its trans- 
formation to the perfect fly. This period was 
selected, as the brilliant colours which adorn it 
had attained their maximum of intensity, and 
the immature wings, with their envelope, were 
most perceptible. It measured eight-tenths of 
