206 CURIOUS HOMES AND THEIR TENANTS. 



little jerks caused hj each stroke of the force pump, 

 which expels a jet of water from the outflow pipe of 

 the siphon." 



Hercules destroying fabled hydra. 



AN ANIMAL ROLLED INTO A BALL, 



THAT LIVES IN THE SOLID ROCK. 



A sea urchin does not look very unlike a small 

 hedgehog or porcupine ant-eater that has rolled itself, 

 as these manmials are sometimes in the habit of doing, 

 into a prickly ball. It must, however, be confessed 

 that an important difference exists in the fact that 

 hedgehogs and porcupine ant-eaters can unroll them- 

 selves, while a sea urchin is no more able to do so 

 than the chestnut burr he so much resembles. 



Bring all the points of a five-fingered starfish to- 

 gether, fill up the spaces left empty with substances 

 similar to those of which the starfish is composed, and 



