PREFACE. 



organic phenomena which may be studied in the pages of the Diary. 

 Correlations exist between the leafing of trees, the germination of seeds, 

 and the temperature on the grass ; between the blossoming of flowers 

 and the appearance of insects ; between the ripening of fruit, the appear- 

 ance of insects, and the temperature in the sun ; between the appearance 

 of insects and their larvae, the ripening of fruit and seeds, and the nesting 

 and migration of birds — all of which are of great scientific interest, and of 

 practical value to persons engaged in rural occupations, as is also a know- 

 ledge of the first appearance of insect pests, with a view to their early 

 destruction. 



To the botanist, entomologist, and ornithologist, and especially to the 

 young naturalist, the Diary will serve as a guide to the localities and the 

 seasons where and when the objects he wishes to study may be found ; 

 and it will supply lists of objects to be looked for on each day of the 

 year. It will also enable him to record the results of his observations 

 in a systematic manner, and where they can be preserved for future 

 reference. 



To all persons, whether living in town or country, the Diary will afford 

 space for recording the results of their out-door occupations, or for such 

 personal observations as show the relation of the human body to the other 

 phenomena recorded. The relation of the growth of children to the sea- 

 sons of the year, of diseases and epidemics to varying conditions of 

 climate, and of periodic phenomena common to men and the lower 

 animals, are of this kind, and are all deserving of careful study. A game 

 and fishing list is introduced in this part of the Diary as being most' 

 agreeable to the other entries, but any other set of observations may be 

 substituted for it. 



The Diary, in conformity with books of a similar kind, commences 

 with the first day of the year, but this is not the beginning of the 

 biological year. Theoretically it ought to begin the day after the winter 

 solstice {i.e., December 22nd), but in our latitudes the climate lags behind 

 the sun's movements. The mean temperature for twenty years at Marl- 

 borough shows that January is the coldest month, and the fourth week of 

 that month the coldest week of the year ; and it is not till the middle of 

 February that the sun's influence is perceptible, and a slight and sustained 

 increase of temperature takes place. The middle of February (St. Valen- 

 tiije's day) may be accepted, therefore, as the beginning of the biological 

 year, and the diary should be kept round the year from that time, the 

 daily accumulated temperatures and rainfalls being corrected by deducting 

 the values representing the day (on February 14th 90-8° and five inches 

 respectively) from the subsequent totals. As I have explained elsewhere, 

 the plants which blossom with us in January and beginning of February 

 belong to the previous autumn, and should be studied in connection with it. 



Collective investigation — that is to say, the systematic observation of 

 the same phenomena by a large number of persons living over a wide 



