132 A NATURALIST'S CALENDAR FOR DORSETSHIRE. 



observe and note down without the requirements of any special 

 scientific knowledge. They refer to the appearances of the first 

 primrose in spring, the first apricot and peach blossoms, the earliest 

 appearance of the swallow, cuckoo, and nightingale, and so on. 



The results of these observations confined to one parish cannot 

 naturally be of much value except to the observer or his neighbours. 

 From it we may fix the limits in the arrival of the swallow, for 

 instance, which are 18 days deduced from 13 recorded observations, 

 or of the cuckoo 14 days in 15 observations of the nightingale 

 21 days in 11 observations, and so on for the other phenomena 

 recorded, but beyond this he cannot learn much. 



By comparison, however, generalisations of various kinds might 

 be effected. For instance, and it is here the value of system I 

 hope to explain to you lies, a printed calendar derived from 

 observations recorded over 10 years from a spot in a distant county 

 gives for the three phenomena mentioned above a smaller limit 

 viz., 15 as against 18 days for the arrival of the swallow, 12 as 

 against 14 days for the arrival of the cuckoo, and 14 as against 21 

 for the arrival of the nightingale. But with these data we cannot 

 establish any inference that the position of the village and the 

 circumstances of its surroundings produce exceptional conditions 

 which cause the movement of birds to vary more than elsewhere. 

 Our facts are not sufficient they are not sufficiently numerous ; 

 they relate only to the migration of a few species, and are only 

 collected at one spot and not over a large area, and, therefore, no 

 deductions of any value can be made from them. What we 

 require is a systematic series of observations made at various places 

 scattered over the county and dealing with a variety of subjects, 

 and extending finally over a considerable period of years. How, 

 then, should a Naturalist's Calendar be constructed for Dorset, and 

 of what should it consist *? This is the question before us. Ere we 

 answer, we may find out what has already been done in this 

 direction by others, and, believing that imitation is the sincerest 

 form of flattery, take, perhaps, a lesson from them. I have with 

 me from the transactions of the Hertfordshire Naturalist's Society, 



