INVESTIGATION OF OYSTER SPAWNING, ETC., MILFORD, CONN. 439 



Table 3. — Water temperatures at Station No. 2, 1926, in ° C. 



The daily range of water temperature varies from 1 to 11.5 degrees and is indica- 

 tive of the continuous fluctuations that occur in these inshore waters. It also shows 

 very well how little value can be given to occasional water-temperature observations 

 in such locaUties. The records given in these tables have been plotted in Figure 5 

 so as to show more clearly the extremes of water temperature for each day together 

 with the daily mean. The maximum, in virtually every instance, corresponds to 

 the water temperature at the time of low water, while the minimum invariably occurs 

 at high water, when the greatest quantity of water has been brought in by the flood 

 tide from the Sound. It is apparent from these graphs that at certain times the 

 daily range of temperature was much greater than the average monthly range, as, 

 for example, on July 6 and 19 and August 20, 1925, and on July 10 and 22 and 

 August 4, 1926, when the daily range of temperature was from 7.5° to 11° C. These 

 periods were foimd to correspond to the times when there were certain tidal 

 conditions, which are discussed in detail in the paragraph on the effect of tide on 

 temperature. 



In order to understand and make clear the causes of the changes in temperature 

 that have been discussed, it is necessary that each important chmatological and 

 hydrographical factor be taken up separately with regard to the effect it produces. 



As a basis for discussion, the normal chmatological data for this region are shown 

 in Figure 6. The monthly means are taken from the records of the United States 

 Weather Bureau station at New Haven, Conn., which is but 9 miles east of Milford. 



