190 



MAMMALIA, REPTILIA, ETC. 



though they are, they seek their own food as soon as 

 they are born. Some of the blennies can wriggle out 

 of the water by means of the free rays of the ventral 

 fins ; and the smooth blenny is especially fond of 

 climbing on the rockwork of the tanks just above the 

 water level. So tamable is this species that Mr. 

 Lloyd says it will even feed when taken into the 

 hand. 



The gobies are a useful and interesting series of 

 aquarium objects, on account of the ease with which 



they can be kept in a 

 state of healthy activity. 

 The largest species is 

 the black or rock goby 

 (Gobius niger), which 

 may be seen in every 

 public aquarium in a 

 very tamed condition. 



Fig. 125. 



It has a kind of " suck- 

 ing fin " on the ventral 

 or under surface, by 

 means of which it can 

 attach itself to the 

 smooth face of the glass, 

 on which it sometimes 

 deposits vast quantities 

 of minute eggs, and then watches them most pertina- 

 ciously. It abounds in our rock-pools, and may be 

 easily captured there by means of a hand-net. 



Ventral surface of the Rock Goby 

 (Gobius niger], showing sucking fin. 



