CHAPTER II 

 THE LOBSTER AS A TYPE OF CRUSTACEA 



THE most noticeable feature distinguishing the 

 Lobster 1 (Fig. i) at first sight from other 

 familiar animals is the jointed shelly armour that 

 encases its body and limbs. Over the fore part of 

 the body this armour is continuous, forming a shield, 

 or carapace, which projects in front, between the 

 eyes, as a toothed beak, or rostrum ; on the hinder 

 part the tail, or abdomen it is divided into six 

 segments, or somites, connected with each other by 

 movable joints. Each of these somites carries on 

 the under-side a pair of fin-like limbs, or swimmerets, 

 the last pair of which (uropods) are much larger than 

 the others, and are spread out at the sides of a middle 

 tail-plate, or telson, forming what is known as the 

 tail-fan. Since the fore part of the body also has a 

 series of paired limbs, constructed, as will be shown 



1 The account given here of the structure of the Lobster 

 applies almost equally well to the River Crayfish or the Norway 

 Lobster. The student is recommended to follow the description 

 with a specimen of one of these animals before him. 



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