150 MARINE AQUARIA FOR ROOMS. 



gas, forced into it from a bladder, to the mouth of 

 which a clean, long tobacco pipe has been fastened, 

 so that it can reach the bottom, might, under some 

 conditions, soon put it to rights. 



Fig. no. 



Halidrys siliqnosa (nat. size). 



A most useful and beautiful animal is the Ormer 

 (Haliotis tuberculata), or " Venus's ear," as it is some- 

 times called. This univalve is common along the 

 shores of the Channel Islands. In the aquarium it 

 is as good as a natural scrubbing-brush for keeping 

 the sides, &c., clean ; whilst it is equally useful in 



