OF THE SKELETON. 



139 



and fourth segments, e, o, and thus we have before us all 

 the organs of locomotion possessed by insects. Although 

 so nearly resembling Phasma in appearance, 

 the species of Mantis are totally different from 

 them in mode of life ; feeding on living in- 

 sects, and displaying great savageness and 

 cruelty of disposition, fighting each other 

 with the most determined courage and fero- 

 city, and using their fore legs, which are 

 peculiarly constructed for the purpose, as 

 weapons of offence : this employment of the 

 fore legs renders it essential that they should 

 possess greater muscular power than those of 

 the quiet Phasma, and if we compare the size 

 of the second segment in these two insects, 

 we can scarcely fail being struck with the 

 difference which they exhibit. 



By examining the Mantis it will be seen 

 that the posterior edge of each segment after 

 the fourth, protrudes over the anterior edge 

 of the following segment, thus the alternation 

 of flexible and inflexible portions of the skin allows not 

 merely a free motion to the right or left, upwards or down- 

 wards, but of increase or decrease in length, at the plea- 

 sure of the insect : contraction is performed by the 

 segments being drawn one within another, and elongation 

 by extending and separating the rings : this action, which 

 is very observable in the bodies of the wasp or honey bee, 

 is represented by the sliding of the tubes of a telescope. 



The names of the thirteen segments of insects, and the 

 limbs which they bear, are as follow ; and in the figures 

 which the author has drawn to illustrate the subject, similar 

 references are invariably used, a plan which will be found 

 to save much trouble, as all confusion is thus avoided. 



