THE IBIS. 



SEVENTH SERIES. 



No. XV. JULY 1898. 



XXVIII.— On a Hybrid Thrush found in Norway (Turdus 

 iliacusx Turdus pilaris). By R. Collett. 



(Plate VII.) 



In December last I obtained a newly -caugbt specimen of a 

 Thrusb, wbich in size and plumage appears to be inter- 

 mediate between Turdus iliacus and Turdus pilaris, and 

 wbicb I believe to be a bybrid between tbese two species. 



The specimen was snared in Faaberg, Norway, tlie 

 soutliernmost district of Gudbranddalen, on the 11th De- 

 cember 1897, togetlier with some examples of T. pilaris. 

 Its stomach contained only berries of the mountain-ash 

 {Sorbus aucuparia). In Faaberg a great portion of the sides 

 of the valleys extends into the subalpine region, and both 

 T. iliacus and T. pilaris commonly breed there. In most 

 of the colonies of the far more numerous T. pilaris one 

 or more pairs of T. iliacus will be found. 



The hybrid specimen, which was quite fresh and uninjured 

 when it came into my hands, was of the following dimen- 

 sions : — Total length, 253 millim. ; length of wing, 131.; 

 length of tail, 89. In size it was thus about halfway 

 between the dimensions of its supposed parents. (Six.un- 

 skinned specimens of T. iliacus measured, on an average, in 

 total length 221 millim., eight of Turdus pilaris 275 millim.) 



SER. VII. VOL. IV. z 



