PARTS OF INSECTS. 33 



tions ; and so likewise do the appendices at the extremity- of the ab- 

 domen. 



The abdomen contains the intestines, tlie ovary, and jiart of the or- 

 gans of respiration: it is affixed to the thorax, and in nio^^t insects di- 

 stinct from it, forming the posterior part of tlie body. 



Cauda, the TuiL An appendage of any iiind terminating the abdomen 

 is usually denominated the tail. These appendages vary in figure con- 

 siderably in different insects, and many tribes are totally destitute of them. 

 They are supposed to be destined to direct the motion of the insect in 

 flight, to serve lor its defence, and for the deposition of its eggs. In some 

 insects this tail is simple, and yet capable of being extended and with- 

 drawn at pleasure ; in others elongated. Some are setaceous or bris- 

 tle-shaped, as in the Raphidia. Tliosc termed triseta have three bristle- 

 shaped appendices, as in the Ephemera. In some it is forked, as in 

 Podiira. When it terminates in a pair of forceps it is called J'urcipnta. 

 In the Blatta and others it is follosa, or resembling a leaf. In the 

 Panorpa it is furnished with a sting, and is called tclij'era : this last may 

 be more properly referred to the next. 



AcuLEus, the Stinii : an instrument with which insects wound and in- 

 stil a poison. The sting generally proceeds from the vmder part of the 

 last ring of the belly: in some it is sharp and pointed, in others ser- 

 rated or barbed. It is used by many insects both as an offensive and 

 defensive weapon : by others it is used only to pierce wood, or the 

 bodies of animals, in order to deposit their eggs. In wasps and bees 

 the sting is known to be retractile. In some insects it exists in the male 

 only, and in others nature has provided the female alone with 

 this instrument : it is not frequently met with in both sexes of the 

 same species, and the far greater number of insects have no such 

 organ. 



ARTUS, the Members. 



Pedes, the Legx. In all insects the legs amount to six, and never 

 exceed that number; and the same is observable of the true feet in the 

 larva; of those insects; the latter have spurious feet to a greater amount, 

 but the true feet do nut exceed six. 



The leg of an insect may be divided into four, or more correctly in- 

 to five, parts : Coxa, the first joint or haunch, at the base; Femur, the 

 thigh; T'/i/rt,the shank; Tarsus, the foot; and Unguis, the claw. Each 

 of these parts is enveloped in a hard case of a horm^ substance, and 

 varies in shape in different insects, the form of the feet in all the kinds 

 being admirably adapted to their mode of life and convenience of their 

 motion. From the different conformations of these limbs it is easy to 

 recognise, even in the dead insect, the mode of life which the species is 

 destined by nature to pursue. Those which have the legs adapted for 

 running or walking have them long and cylindrical : the thighs of the 



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