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Show ENTOMOLOGY j Edited by Prof. E. G. Titus, State Agricultural College. -WHY WE NAME THINGS. There exists among all animals certain cer-tain characters which arc not possessed pos-sessed by plants or minerals. Hence we first have three divisions that arc known as the Animal Kingdom, the Plant or Vegetable Kingdom and the Mineral Kingdom. By far the greater number of Natural objects that we have occasion to notice wc can readily place in one of these divisions or Kingdoms. In the Animal Kingdom there arc so many forms presented to our view that wc find it necessary to have some kind of a classification in order to study them properly. It has been estimated es-timated that there arc now living upon up-on the earth more than a million and half species of animals. The immensity immen-sity of the problem may now be realized real-ized and t is not to be wondered that a system of classification had to be built up as the years went by in order, that wc nvoy properly place the dif- 0 fcrcnt forms that have been recognized recog-nized and described. Some animals arc so simple in form and have such slight changes in tjicir life-history that they arc considered as occupying the bottom of the list. These arc animals composed of a single sin-gle cell. A cell is a minute mass of substance known as protoplasm, having hav-ing life, and the ability to reproduce, to feed and usually to move. The next members of the group have a more complex structure, but arc still very simple and so there -are arranged groups to contain animals having some characteristics in common; each group as we pass up the list having more and more complex "characters; in habits, in form, in its methods of life and in its relationship to surrounding sur-rounding things, than the one just before be-fore it. It is impossible to limit these groups absolutely because there are often animals in each group which are either a little too highly developed to be put in the next lower group, or, on the other hand1, are so much more complex than the majority of the members in the group in which they are placed as to be almost (but not quite) plaGdd in the group ahead. Over half way up this list placed above the true worms but just below the true shells, stands the group to which the Insects belong. They are only one of several lesser groups that belong in this large group. Some bf the others arc almost as well known to most of us as arc the insects, for here belong the crayfish and lobsters, , the scorpions, the spiders and mites (red spider), and the centipedes and millipedes (thousQnd-lcggcd worms). i All of the animals belonging to this group have the common character of a body composed of several more or less similar rings, some of the rings having upon them jointed legs. If you will examine a crayfish or a lobster you will find that it has at least five pairs of legs, rarely more, never naturally less. A look at a scorpion scor-pion will show you four pairs of legs, i a spider also has four pairs of legs, but its front pair does not grow large !j strong claws or pincers as do thc crayfish and the scorpion. A mite, our brown mite or red spider, for in-stance, in-stance, has four pairs of legs and is I very closely related to the spider. The ticks belong with the mites. The centipedes cen-tipedes have a single pair of legs to each one of the segments or rings of the body that bears legs, While the j millipedes, or thousand1 legged worms, 1 have two pairs on each ring that has any legs. The centipedes arc really j bcifcfvcial since they feed almost entirely en-tirely upon insects and other minute animals that live under bark, stones or logs. Some of the centipedes have poison glands which open through the claws of the first pair of legs and can really indict, a rather serious injury, 'but those species which are large enough to cause much trouble nearly all live in warm regions. The thous- nL and-leggcd worms arc never poisonous, poison-ous, but sometimes cause injury to plants by feeding upon the young and tender shoots. It can readily be seen that we cannot can-not continue on down in our divisions of the large Animal Kingdom without something more definite than the term group, larger group and smaller group; hence, to each one of the divisions di-visions of the kingdom has been ap-. ap-. nUgd the term branch and each - branch given iTdistinctive name. The ontt to whioh the inseGts spiders, mites fliul such closely related animals ani-mals belong is known as Branch Ar-1 Ar-1 thropoda. This is not a hard word to 1 remember when wc know its mean- ing which is simply jointed feet. HI |