238 THE ZOOLOGIST. 



consumed as food in China, where it is looked upon as a luxury 

 under the name of " trepang." 



The true worms, or Annelides, are indispensable to fisheries. 

 They are divisible into the Abranchiata, or gill-less forms, which 

 contain Earthworms and Leeches ; and the Branchiata, or gilled 

 kinds, which include Tubeworms and Sandworms, &c. The 

 Annelids comprise many forms largely employed as food for fish, 

 and some, as the Lobworm, are very useful for bait ; others, as 

 Leeches, are detrimental to fish. 



Insects have been said to be Nature's most favoured creation, 

 having combined in them all that is beautiful and graceful, inte- 

 resting and alluring, or curious and singular, in every other class 

 of her (Nature's) productions. They are placed by entomologists 

 in three great divisions, in accordance with whether they pass 

 through a metamorphosis or not, and if they do, whether such is 

 complete or incomplete. Many insects form food for fishes in 

 some stage of their existence, while others are very destructive to 

 fish-eggs. 



Crustacea are most generally known as Lobsters, Crabs, 

 Shrimps, Prawns, &c, and are variously divided by different 

 zoologists. All Crustacea are water-breathers, some having eyes 

 placed upon footstalks, while in others they are without stalks, 

 being sessile or immovable. All undergo successive moultings or 

 changes of shell, at which times lost parts become renewed. In 

 the earlier stages of the lower crustaceans they emerge from the 

 egg as a small body, having a central eye and two pairs of limbs 

 (so-called zoea stage), while, as they gradually attain the adult 

 stage, new segments and new limbs appear. In their earlier 

 stages Crustacea become a most important article of food for 

 fishes, while their adult forms are likewise esteemed by the more 

 predaceous kinds. 



The class Amphibia comprises Newts, Frogs, and Toads, 

 and in some localities Frogs play a not unimportant part in 

 fisheries, as they not only devour the ova, but likewise the fry, 

 while their own spawn in turn becomes food for fish ; and a Frog 

 is highly esteemed by many fresh-water fishes. Reptilia (or 

 Reptiles), including Tortoises, Turtles, Terrapins, Snakes, Lizards, 

 Crocodiles, and Alligators, are more destructive to fish than are 

 the true amphibians. The Chelonians are usually divided into 

 the Swimming Turtles, the Mud Turtles or Soft Tortoises, and 



