GOBIES. 



197 



The gobies are hardy little fishes, and are able 

 to withstand the prejudicial influences that are 

 inseparable from even the best-regulated aqua- 

 rium. Some three or four are sufficient in 

 number, and impart to the tank a liveliness that 

 is very pleasing. The ventral fins of the gobies 

 are so formed that they can be pressed together 

 and used as a sucker, by means of which they 

 can adhere firmly to the glass forming the sides 

 of the aquarium, or to the rocks and stones of 

 their native sea. The rapidity, too, with which 

 a goby affixes itself to the glass is quite sur- 

 prising. These little fish are terrible enemies to 

 the shrimps, for they feed greedily either on the 

 eggs themselves, or on the young shrimps when 

 they have just emerged from the egg. They also 

 feed much on the animalcules of various kinds 

 that throng the alga, and so may be conveniently 

 fed by placing in the tank a handful of freshly 

 gathered ulva, enteromorpha, or indeed any of the 

 sea-weeds whose growth is sufficiently dense to 

 afford shelter to the animalcules. By the aid of 

 a lens, the tiny creatures may be seen coming by 

 thousands out of the floating sea-weed, and 

 snapped up almost as fast as they show them- 

 selves. 



The Black Goby (Gohius niger) may also be 



