Vo, 'l9i9 XVI ] Lewis, Winter Robins in Nova Scotia. 213 



From the first graph it is readily apparent that few Robins 

 were noted in the province prior to the middle of January. After 

 that time the number seen increased rapidly, reaching its maximum 

 about February 1, and decreasing a little more gradually until 

 about February 20, after which date few Robins were seen. On 

 account of the scarcity of observers, before mentioned, this line 

 does not show the total number of Robins which were present about 

 the inhabited parts of Nova Scotia in any week, nor can its rela- 

 tion to such total numbers be readily determined. It does serve, 

 however, as a moderately correct indicator of the relative abun- 

 dance of the Robins about the inhabited parts of the province in one 

 week as compared with another. 



The graph indicating the weekly snowfall appears as a line of 

 abrupt changes and sharp angles, showing that the variation in the 

 snowfall from week to week was very marked. Somewhat con- 

 trary to expectation, no relation between this line and the Robin 

 graph appears to be traceable. It is possible that, if the average 

 depth of snow on the ground in each week could be depicted graphi- 

 cally, the line thus formed would show more direct relation to the 

 weekly abundance of Robins, but, unfortunately, no data from 

 which such a graph could be prepared are available. 



The temperature graph appears to correspond very well with 

 the slopes of the Robin graph, especially in the part of the winter 

 prior to February 20. A period of low temperature in the week 

 ending January 5 is found to correspond with a noticeable increase 

 in the number of Robins reported, while higher temperature during 

 the week ending January 12 accompanies a decrease in the number 

 of Robins seen. From January 12 to February 2 increasingly 

 lower average temperatures are contemporaneous with an increas- 

 ing abundance of Robins observed, and the extremes of both graphs 

 are reached in the same week. In the week ending February 9 

 both lines fall slightly lower, and in the next week there is a very 

 considerable decline in both. From that time on the relationship 

 appears less close, for a reason hereinafter stated. Such a close 

 correspondence between the two lines as has been pointed out, 

 however, seems most unlikely to be wholly fortuitous, and would 

 appear to indicate that temperature is a greater factor than had 

 been supposed in causing these buds to seek the neighborhood of 

 man. 



