Daphnia pulicaria. 



343 



deeper levels at the station. Under these conditions the mem- 

 bers of this species which ordinarily live between the station 

 and the shore become driven out from their ordinary place of 

 abode, and the numbers at the observing station are corres- 

 pondingly increased. Thus on August 21, 1895, the number of 

 this species caught was 493, a number not far from the average 

 of the month up to that time. On the next day, the wind being 

 strong from the southwest and the thermocline lying at 

 an unusually low level, the number caught was 2,600. On the 

 following day 954 were taken, and four days later only 85. The 

 following table shows the details. 



Table XIX. 



Date. 



Wind. 



Depth. 



Temp. 



No. D. pulicaria. 



1895. 









Above 9 m. 







9m. 



21.4° 



9-12 m. 480 



Aug. 21 





12 m. 

 15 m. 



18.4° 

 15.4° 



12-15 m. 5 





15-18 m. 5 







18 m. 



13.8° 





Aug. 22 



Southwest. 











Above 9 m. 90 





Strong all day . . . 



9 m. 



21.7° 



9-12 m.2,120 







12 m. 



20.4° 



12-15 m. 360 







15 m. 



17.3° 



15-18 m. 18 







18 m. 



14.7° 



Above 9 m. 90 



Aug. 23 



Nearly calm 



9 m. 



22.0? 



9-12 m. 640 







12 m. 



20.8° 



12-15 m. 220 







15 m. 



14.8° 



15-18 m. 40 







18 m. 



13.8° 





Aug. 27 



Calm 



9 m. 

 12 m. 



22.0° 

 20.8° 



Above 9 m. 







9-12 m. 







15 m. 



17.3° 



12-15 m. 80 







18 m. 



13.9° 



15-18 m. 5 



In September of the same year 415 specimens were taken on 

 the 18th, 2980 on the 22nd, and 3615 on the 25th. The condi- 

 tions of temperature in the deeper water were much the 



