ON THE GREAT GREY SHRIKE. i) / 



Introduction, p. xxi). It remained then for Prof. Collett, of 

 Christiania, to show, as I think, conclusively (* Ibis,' 1886, pp. 

 30 — 40), that in North-western Europe, at any rate, the two 

 forms, L. excubitor and L. major, are so nearly related that a 

 hybrid race prevails. Apparently, when we cross the Urals, we 

 only meet with the typical and thorough-bred single-barred bird 

 known as L. major. 



But the birds which visit Great Britain from Scandinavia 

 and Western Russia are so much cross-bred that it is almost 

 impossible to distinguish the immature and female specimens. 

 It seems to me that we should accept this fact, and abandon the 

 attempt to distinguish between the two forms, which, according 

 to Prof. Collett, interbreed to so large an extent. Whatever 

 decision may be arrived at by others, I propose, in the present 

 paper, to treat the two species as one. This renders it possible 

 to speak of the immigration into Britain of what may be simply 

 designated L. excubitor. 



I have carefully examined all the instances recorded in ' The 

 Zoologist.' Excluding from consideration numerous cases in 

 which writers have not taken the trouble to state the arrival of 

 Shrikes with scientific precision, I find a balance in our favour 

 of eighty-nine distinct occurrences between 1843 and 1882. 

 Apportioning the numbers to the months, the following results 

 are reached : — January, nine birds ; February, eight ; March, six ; 

 April, six; May, one; September, one; October, seventeen; 

 November, twenty-six; December, fifteen. It would be sup- 

 posed from this that the largest number arrive in November, and 

 this is possibly the case. Yet we have it, on the authority of 

 Mr. Cordeaux, that in 1876 no less than fourteen Grey Shrikes 

 were identified at Spurn (twelve of the number having been 

 shot) during October (Zool. 1877, p. 10). 



Another fact brought out by these statistics is that this Shrike 

 is very variable in regard to the numbers in which it annually 

 visits us. Whilst a few individuals occur along favourite " fly- 

 lines" every year, in some years their number is increased 

 tenfold. Those which winter with us for the most part lead 

 lives of solitude, frequenting a particular beat of country for a 

 week or two at a time, during which the familiar outline of the 

 Butcher-bird may at any time be detected upon the top of some 

 naked tree ; scouring the hedgerows for field mice, shrews, and 



ZOOLOGIST. MARCH, 1891. I 



