THE PUBLIC AQUARIUM 



291 



Tanks containino- live fishes must be aerated during- sliipment, 

 and this is accomplished usually by frequent lifting; of water with 

 a dipper and pouring back slowly. The amount of aeration neces- 

 sary depends upon the numl^er of specimens in the tank. Crowding; 

 is dangerous. During railway trips the use of a hand-operated air 

 ])ump, with rubber-tube connections to each tank, serves to lighten 

 the labor of aeration. The air pump in use at the New York 

 Aquarium has two cylinders 3 by 2 inches, the upright lever being 

 between and above the cylinders. 



Fig. 29. — Introducing oxygen from the steel cylinder into the glass jar 

 TRANSPORTING FISHES WITH THE AID OF OXYGEN 



The use of oxygen should not be overlooked in connection with the 

 transportation of aquarium specimens. We have employed it suc- 

 cessfully on many occasions. Numerous small fishes and inverte- 

 brates have been sent from the New York Aquarium to Germany — a 

 nine-day trip — in wide-mouthed glass jars without loss.^ Sixteen 

 3-liter glass jars were filled with water and the specimens introduced. 

 The jars were then inverted under water and oxygen gas introduced 

 to replace the water until the jars were about one-third full of the 

 oxygen. The jars were then corked tightly and covered with parch-* 

 ment to prevent any escape of the gas. 



Large numbers of trout fry have been sent from the aquarium in 

 open shipping tanks fitted with rubber tubes connected with an 



3 Bulletin, New York Zoological Society, November, 1910, pp. 701-702. 



