386 HOMES WITHOUT HANDS. 



larva has a much larger range of movement. In the ordinaiy 

 species, the creature holds itself to the extremity of the case by 

 means of hooks at the end of its body, which can grasp with 

 some force, as any one knows who has pulled a Caddis larva 

 out of its house. But when the case is fixed, the abdominal 

 claspers of the larva are attached to a pair of long foot-staJks, 

 so that the creature can extend its body to some distance from 

 the entrance of the tube. 



We now turn to the warmer seas, and shall there find some 

 most magnificent examples of subaquatic homes. 



Our first examples of these wUl be the wonderful creatures 

 which are classed together under the general term of Corals, 

 and which are so familiar to us either in a manufactured state 

 or as ornaments for the drawing-room. How vast are their sub- 

 marine labours is evident from the enormous " Coral-reefs " 

 which they raise, and which form great islands whereon an 

 army can live, and inlets wherein a fleet can ride securely at 

 anchor. 



Before proceeding further in the history of the Coral and its 

 submarine home, we wiU see how it extends itself with such 

 wonderful rapidity, and what is the process that enables fresh 

 colonies to establish themselves, and existing colonies to spread 

 themselves — both these operations being conducted on different 

 principles. 



How the Coral grows is a problem which was unsolved until 

 a comparatively late period. Not only were naturalists ignorant 

 of its development, but they did not even know in what king- 

 dom to place it, whether vegetable or mineral. Opinions were 

 long divided on this point, the men of greatest reputation in- 

 clining to the belief that it was mineral, while a very few 

 thought that it must be vegetable, and that the flower-like rays of 

 the polype were veritable submarine blossoms. But when a more 

 careful observer announced that the Coral was really the produc- 

 tion of an animal, both parties united in ridiculing his theory, 

 and for a while the animal origin of Coral was put aside by 

 the scientific world. Truth, however, prevailed, as it always 

 will do, sooner or later, and every one now-a-days knows that 

 Coral is the production of animated beings. 



