MOVEMENTS OF HERRING AND OTHER MARINE FISHES. 317 



such experiments the effect of advancing civilization and industry 

 upon the presence or absence of a species in any locality. The 

 movements of the fishes must be known as well as the cause 

 therefor, before we can intelligently approach the question of 

 capturing them in quantities. 



II. Material and Methods. 

 I. Stock of Fishes. 



The material used in these experiments was chiefly the fry 

 of the herring (Clupea pallasii Cuvier) 6 cm. (23^ in.) common 

 in Puget sound. The fry were caught on July 2 and were kept 

 in a float car anchored in a good tide and until July 22 practically 

 none of the fish died except during the first few days when those 

 probably injured in catching were the chief victims. A few soles 

 {Lepidopsetta bilineata Ayres) secured on July 4 at Fisherman's 

 bay, Lopez Island, were kept in the same car. A few young hump- 

 back salmon (Oncorhynchus gorbuscha Wal.) 7 cm. (2^ in.) long 

 were secured at sea, through the courtesy of Dr. E. Victor Smith 

 on June 30, at Turn Island and were not used after July 8 as they 

 did not appear to be in normal condition after that date. A 

 single Cottid {Oligocottus macidosus Girard) was used in killing 

 experiments. The soles and herring appeared to be in essentially 

 as good condition at the end of the period of work as at the 

 beginning. 



2. The Water Supply of the Station. 



Experiments were run in which both fresh and salt water were 

 used. Thus it is necessary to consider the character of both. 

 The fresh water in use during the summer of 1914 was supplied 

 by the village of Friday Harbor and came from deep wells. 

 Owing to the rocky character of the ground in the vicinity, it 

 was impracticable to bury the pipes and the temperature varied 

 greatly with the weather, night, day, etc. The highest tem- 

 perature noted was 24° C. The water contained an excess of 

 gas which escaped in a cloud of bubbles when it was withdrawn 

 from the tap. This was neither oxygen nor carbon dioxide and 

 gave no odor which points to the conclusion that it was nitrogen. 

 The water was distinctly alkaline to phenolphthalein, free carbon 



