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Springtails and Fishmoths — Part 1

(Order Thysanura.)

The insects of this order are usually of very small size, and are wingless and have practically no metamorphoses. They comprise the little insects known as springtails, bristletails, fishmoths or slickers. They have three pairs of legs, the mouth-parts, often hidden, are formed for biting, and the skin is delicate. The order is supposed to comprise the most generalized or simplest forms of insect life and although there is some reason for considering that they are degenerate insects the consensus of opinion is that they are living representations of primordial insects. Some of them possess a very remarkable leaping arrangement in the shape of a spring-like process on the under side of the abdomen, which enables them to jump in an extraordinary way, some of them have long abdominal appendages or processes at the end of the body, and still others have short leg-like processes on the under surface of the abdomen. The order as at present understood comprises two suborders, namely the Cinura and the Collembola. Formerly some curious creatures belonging to the genus Scolopendrella were considered as belonging to this order and were placed in a suborder by themselves--the Symphyla--but it is thought now that these little creatures are more closely related to the Myriopoda than to the true Insecta.

The two remaining suborders may be separated as follows: With bristle-like and many-jointed appendages or forceps at the end of the abdomen, which is composed of ten segments and does not possess a sucker on the ventral side. . . .Suborder Cinura.

With a forked sucker on the under side of the first abdominal segment, and the abdomen, which is composed of not more than six segments, furnished with a spring-like apparatus near the tip, or without appendages. . .Suborder Collembola.