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ORDER LEPIDOPTERA (BUTTERFLIES AND MOTHS). 

 CHAPTER IX. 



THE METAMORPHOSES OF THE LEPIDOPTERA. 



Characteristics of the Order EGG STATE Structure and Development of Eggs LARVA STATE Shape and Structure- - 

 Stinging Larvre Internal Anatomy Food Enemies Growth and Development METAMORPHOSIS Pupation of 

 Vanessa urticce Of other Butterflies Of Moths which form a Cocoon PUPA STATE Structure of Pupa 

 Development Emergence of the Imago. IMAGO, OR PERFECT STATE "Wings Neuration Scales Legs Head and 

 Body Internal Anatomy Food Senses Geographical Distribution Collecting Killing Setting Relaxing 

 Localities. 



THE order Lepidoptera, or Scale- winged Insects,* includes the Butterflies and Moths, of which at 

 least fifty thousand species have already been described. They may readily be distinguished from 

 all other insects by their being provided with four wings, clothed with scales, in the perfect state. 

 Their metamorphosis is complete that is, they pass successively through the four stages of egg, 

 larva (or caterpillar), pupa (or chrysalis), and perfect insect. These changes we have now to 

 consider. 



The parent Butterfly or Moth lays her eggs on the plant or other substance which is best suited 

 for the food of the larvae when they hatch. Some species lay their eggs singly, while others lay them 

 in a cluster, like the Gold-tail Moth, which covers them with down plucked from her own body, or 

 the Lackey Moth, which glues them in a ring round the small branch of a tree. In any case, 

 they are always so placed as to ensure the safety and comfort of the larvae. 



The eggs are very interesting microscopic objects. They are covered with a hard shell, so that 

 they are not easily injured, and their shapes and colours are very various. Some are globular, others 

 are egg-shaped, or resemble cheeses, barrels, turbans, &c. Some are smooth, but they are more frequently 

 ribbed, fluted, or striated in such a manner as to form exceedingly elegant and complicated patterns. 

 They are most often greenish, but are sometimes brown, blue, red, or yellow, and are not 

 ^infrequently spotted or striped. 



When the eggs are laid they are perfectly opaque, and the interior is divided into two layers, 

 not always sharply differentiated from each other. The inner portion, however, is more liquid than 

 the other, and in this arise ' amo3boid cells," or bodies of an irregular star-shape, which appear first 

 at the upper end of the egg, and multiply until they reach the surface, when they become globular in 

 form, and gradually extend all over it. At the same time they multiply downwards, at length 

 becoming conglomerated into a spindle-shaped mass, in the centre of which appears a longitudinal 

 streak. 



After this stage is reached, the development of the embryo proceeds rapidly, and when the 

 infant larva is fully formed the egg-shell frequently becomes semi-transparent, so that the occupant 

 may be seen coiled up inside. The duration of the egg-state is sometimes variable, even in 

 the same species ; for when two or more broods of an insect appear in the course of one season, 

 the eggs which are laid in the summer hatch in a few days, while those laid by the last autumn 

 brood do not hatch until the following spring. But in such a case the larva is often fully 

 developed in the autumn, and lies dormant in the egg during the winter, ready to burst from its 

 prison as soon as the vegetation of the next season shall be sufficiently advanced to provide it with 

 appropriate food. Sometimes, too, when young larvae are hatched in autumn, they retire at once to 

 winter quarters, and eat nothing until the following spring. 



All eggs, however, do not arrive at maturity. Unfertilised eggs do not usually hatch, although 

 parthenogenesis sometimes takes place in the Silkworm and other large Moths, while it seems to be 

 almost the rule among some of the smaller Moths, especially in the genus Solenobia, the wingless 

 case-bearing females of which may go on reproducing their kind for generation after generation, like 

 Aphides, without the appearance or intervention of any male. 



Lepidoptera are very subject to the attacks of parasites in their earlier stages, and many of their 

 eggs are destroyed by small four-winged flies belonging to the order Hymenoptera and the family 



* Greek : lepis, a scale ; pteron, a wing. 



