. Agricultural news. Agriculture -- West Indies; Plant diseases -- West Indies. Fig. 43. Cockroach. (U. S. Department abdomen. The legs are attached to the thorax, one pair to each segment; khe fore and hind are attached to the second and third segments, res- pectively. The head and abdomen have no of locomotion. To the head are attached the mouth parts, and the ^antennae wliicli are sen- sory organs. 'J'he abdomen also sometimeshas sensory organs. Fig. 13 shows the cockroach and the attachments of wings and In the case of most insects, tlie adult deposits eggs from which
. Agricultural news. Agriculture -- West Indies; Plant diseases -- West Indies. Fig. 43. Cockroach. (U. S. Department abdomen. The legs are attached to the thorax, one pair to each segment; khe fore and hind are attached to the second and third segments, res- pectively. The head and abdomen have no of locomotion. To the head are attached the mouth parts, and the ^antennae wliicli are sen- sory organs. 'J'he abdomen also sometimeshas sensory organs. Fig. 13 shows the cockroach and the attachments of wings and In the case of most insects, tlie adult deposits eggs from which the young are hatched. There are instances, however, among thes3 animals, in which the young arc already hatched from the egg at the time w riculturt Fig, 44. I!ean Lkak 1!ollei:. egg, it goes through changes and before reaching the fvdly developed or adult condition. This change and development is called the metamorphosis. may be either complete or incomplete. This does not mean that development stops short of the [jcrfect insect, in the case of insects which have incomplete metamorphosis, but rather exjjresses a general dilierence between these two kinds of development. Insects which have an incomplete metamorphosis are something like the adult when they are first hatched from the egg. (Fig. 43, young (c) and adult (ii and //) cockroaches.) They are, of course, much smaller, and without wings, but in general form they give an idea of what the}" will be like when they are full-grown. Insects which have a complete metamorpliosis are verv dif- ferent, when first hatched, . from the adult form into which they finally develop. Such insects have four distinct stages, or period.'', in their lives. are, the egg, the larva, the (lupa and the imago. The egg is the first stage in the (Icvelopment of a generation, and the larva is the next. The larvae of the butterflies and moths are called caterpillars; of beetles, grubs; and of files, maggots
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