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A RT. 11. Observations on the early departure of some species of 

 Sylviadae, or Warblers, during the last Summer. By P. J. 

 Selby, F.R.S.E. F.L.S. F.G.S. &c. 



Having, for several years past, directed my attention to the 

 migratory movements of the feathered race, as connected with 

 their economy, and noted, with some degree of accuracy, the 

 stated periods of arrival and departure of our various periodical 

 visitants, and, more particularly, of such as are appropriately 

 called summer birds of passage, I discovered, with no incon- 

 siderable surprise, during the course of my observations this last 

 season, that several species of sylviadce, or warblers, prematurely 

 deserted their summer haunts, and quitted the northern districts 

 of the island, at least two months before the time they usually 

 leave us, to commence their equatorial migration, or departure 

 for warmer winter quarters. The cause of so striking a deviation, 

 at variance with any previous observations, I can only attribute 

 to the effects produced upon their delicate and sensitive consti- 

 tutions by a season unusually wet and cold, during a period of 

 peculiar importance, as regards the functions and economy of 

 these interesting creatures, as well as a deficiency of food, the 

 result of the like inclemency of the weather. But, as a brief 

 detail of the facts, as they offered themselves to my notice, may not 

 be unacceptable to those who find amusement from, or are engaged 

 in similar pursuits, I shall proceed to give them as they occurred. 

 Towards the regular period, when the majority of our summer 

 visitants are first seen in the northern districts of the kingdom, 

 viz. between the 25th of April and 5th of May, I did not, this 

 last spring, observe any deficiency in the usual proportions of 

 the various species which are known to extend their polar migra- 

 tions to this latitude. Of this I could form a pretty accurate 

 opinion, from the numbers seen dispersed in our woods, groves, 

 and hedges, as well as by the frequency of the songs and peculiar 

 note-calls of each individual variety. Shortly after the arrival 

 of the females, which does not take place, in many instances, 

 till a week or ten days after the first appearance of the other 

 sex, they commenced nidification, and, towards the middle of 

 May, several nests were found containing eggs. Almost imme- 

 diately afterwards, a series of wet weather ensued, which con- 

 tinued, with little or no intermission, and with scarce an inter- 

 vening gleam of sunshine, till after the 10th of July, the fall of 

 rain at times being particularly heavy, and attended with frequent 

 storms of thunder and lightning. It was observed, during June, 

 that the young of several species, particularly of such as build 

 an open, flimsy nest, as the blackcap, pettychaps, &c. and which 

 is generally placed in situations affard n^ little protection from 

 the weather, were all drowned, or ])erisned ; and where they 

 contained eggs, these were cold and deserted, the parent birds 



