NO. 9 MARINE INVERTEBRATES, ALASKA — MacGINITIE 59 



fig. 2) which not only protected the flame of the stove from the wind, 

 but also provided shelter for the workers. 



The advent of late spring brought another problem — dilution of 

 the ocean water with the fresh water from the melting ice. With sev- 

 eral feet of fresh water floating on top of the salt water, practically all 

 the planktonic animals were killed when the net was drawn to the 

 surface. In an attempt to overcome the lethal effects of the fresh 

 water, a water-sample bottle was lowered by means of a long pole to 

 a depth of lo feet and the salt water thus obtained was poured into 

 the flask at the end of the plankton net before the latter was lowered. 

 The heavier water in the flask prevented the fresh water from enter- 

 ing, so that the majority of the planktonic forms could be brought to 

 the surface alive. The dead ones, mostly chaetognaths, were probably 

 those that had ventured into the upper layer of water and were already 

 dead when taken in the net. 



CARING FOR ANIMALS IN THE LABORATORY 



As mentioned above, dredged material was partially sorted on the 

 deck of the boat (pi. 4, fig. i). The material was then carried to the 

 laboratory, where it was carefully separated. Because of the higher 

 temperature and the absence of running salt water, the specimens could 

 not be kept alive in the laboratory for any great length of time. They 

 were sorted into pans and large and small finger bowls and placed in 

 an unheated anteroom until they could receive further attention. To- 

 ward the end of the dredging season the anteroom would become too 

 cold, especially at night, and the containers were placed on the floor 

 near a door inside the laboratory room. A thin coating of ice over 

 the pan or bowl was not fatal to the animals. 



In 1949 a kerosene-operated refrigerator was available. It formed 

 an excellent storage place for specimens — when it worked. Unfortu- 

 nately, it could not be relied upon, and during the night it might be- 

 come fatally warm, or it might freeze solid the contents of pans and 

 bowls. A walk-in refrigerator that became available for use later in 

 1949 made it possible to keep some of the animals for several weeks, 

 thus allowing more time for anesthetization and preservation and for 

 examination of living animals. 



When time permitted, colored 2-by-2-inch slides were made of the 

 live specimens and later sent to the taxonomists working with the 

 subjects. Taxonomists seldom see living specimens of the animals 

 with which they work, and consequently have no idea of their color 

 or appearance before they are preserved. 



