RICHES OF THE TIDAL CUERENTS. '85 



and caVefully rinse their nets in the small tubs, on the chance of getting 

 something worth having. It is by this sort of pleasant sea-prospecting 

 that we have learned how rich are the tidal currents setting into Narra- 

 ganset Bay in representatives of all the crowding pelagic life of the Gulf 

 Stream ; and if Mr. Agassiz neglects to drag his nets on the incoming tide, 

 it is a small matter, for the outgoing rush leaves a thousand sea - born 

 youngsters captives in the pocket-like cove just under his windows, where 

 they have been entrapped and may be scooped up at leisure. 



Returning from such an excursion, the buckets and tubs containing 

 the " net result" are brought to the laboratory and sorted out. The visitor 

 then would find the long central tables covered with glassware — jars and 

 pans and bowls, white and clear as crystal, capacious as if to hold punch 

 for the Chaplain of the Fleet, every one with a mouth as big as its-body, 

 or even bigger. Some of these high, straight-sided, flashing jars will hold 

 several gallons; some of the shallow ones are like six-quart milk-pans, and 

 the sizes of the others lessen to the minimum of a watch crystal, where a 

 single egg, or gastrsea larva, or dancing animalcule may be isolated from 

 his fellows. This glassware is all made to order for the laboratory and 

 for the Cambridge Museum. It is altogether unequalled for the purpose, 

 since it is capacious, clean, transparent, and not affected by sea-water as 

 metal or wood would be, while it is cheaper, lighter, and more handsome 

 than porcelain. 



Having roughly sorted and cared for the dredgings that same night, 

 the next morning the student examines them more carefully, and arranges 

 for preservation the specimens which he especially desires to keep alive. 

 The method will depend upon the age, character, and known hardihood of 

 the object, but the two requisites in all cases are cleanness of water and 

 constant aeration. Turning off the water from one of the pipes, a rubber 

 tube from the air-main is led to it, and it becomes an air-pipe. The jar 

 containing the living specimen is placed on that part of the table at which, 

 by means of the tiles underneath, it can be seen to the best advantage ; a 

 small rubber tube attached to a faucet on one pipe is made to supply to it 

 a steady stream of clean sea-water, and another tube brings fresh air to 

 replace the oxygen exhausted by the animal's respiration ; the overflow 

 takes care of itself, and there is no further trouble. 



But this- simple 1 proceeding can be trustea" only in the case of large, 

 mature, tough animals, such as rarely have the honor of reposing in these 

 scientific precincts. More gentle treatment is usually required, and the 

 methods now successful have only beeii learned through long and costly 

 experience. 



