Ig-i delations of the Structure of 



from all this unharmed, and, by a simple and beautiful con- 

 trivance, are enabled to abide their time, to exist till their 

 destiny is complete. They are provided with an exterior 

 skeleton, a covering which wraps them as a mantle and shields 

 them from harm. 



The covering of annulates is completely bony; it is, in 

 every respect, a substitute for the internal skeleton of verte- 

 brates : like that, it serves for the attachment of the muscles 

 and support of the whole frame. It bears uninjured the con- 

 tact of the roughest and hardest substances. It enables its 

 possessor to endure that rough usage which the more perfect 

 developement of the organs of the senses in vertebrates en- 

 ables them to avoid. When we consider the destiny of annu- 

 lates, principally food for each other, or for larger animals, 

 we cannot wonder that the same nicety of reasoning power 

 and of sensation, which vertebrates enjoy, has not been given 

 them. To what good purpose would it have tended, had 

 nature furnished creatures so obviously the sport of wind and 

 wave, so obviously liable to continual loss of limb, so ob- 

 viously designed the living food of others, with that constant 

 apprehension of danger, and that acute sensation of injury, 

 which we ourselves possess? Certainly to none. Their 

 brain does not reason, their covering does not feel. This 

 bony covering or skeleton of annulates gives them shape, and, 

 like the skeleton of vertebrates, affords the naturalist some of 

 the best characters for distributing them into groups. It is 

 transversely divided into thirteen segments, or rings ; whence 

 the term annulate. To each of these rings names have been 

 lately given by Mr. Newman, in the work before alluded to, 

 the Entomological Magazine. Attached to these rings are 

 the organs of locomotion ; and the number, position, and de- 

 velopement of these are very various ; and a knowledge of 

 these variations is, consequently, not only highly interesting, 

 but absolutely essential to the right understanding of the 

 economy and classification of these wonderful creatures. 



The muscles, in annulates, are very various in their pro- 

 portions; we shall, however, always find them beautifully 

 adapted to the labour they have to perform ; and their degree 

 of developement operates immediately on that part of the 

 skeleton which covers them, by a visible increase or decrease 

 in size of the bony plates of which each segment is composed. 

 It not unfrequently happens in glowworms, moths, &c., that, 

 in the same species, one sex is provided with wings and the 

 other sex wants them entirely : in these cases we find that, in 

 the females, there is a tendency to equal developement of all 



