350 THE ZOOLOGIST. 



1*25 in., culmen *5 in., hallux *34 in. ; Shetland (4), Mr. Seebohm, average 

 wing ]*91 in., tail T18 in., culmen -58 in., hallux "41 in. ; Common Wren, 

 Mr. H. Saunders, average wing 1*9 in. One noticeable point here is the 

 extreme shortness of tail, apparently characteristic of the Shetland Wren. 

 Another is the almost absolute identity of wing measurements with the 

 Common Wren. As regards the amount of barring, this is, as Mr. Seebohm 

 himself says, dependent to a certain degree upon season, and the Shetland 

 Wrens were killed in June, when the plumage would be much abraded, as 

 is clearly indicated by the shortness of the tail. In colour, and also in the 

 amount of barring of the Copenhagen specimens, neither Herr Winge nor 

 myself were able to detect any difference between the Iceland, Faroe, and 

 Danish Wrens, but the Italian bird was decidedly paler. If we are going 

 to draw fine distinctions, the beak and legs are the only safe guide, and even 

 in these respects there is no absolute rule, as one of the Faroe birds had 

 little or no superiority in size over the Danish with regard to its culmen 

 and hallux. Looking at the Shetland group on the map, a long way east 

 of Faroe, and less than 200 miles from the Norwegian coast islands — 100 

 miles less than between Flamborough Head and Heligoland — and remem- 

 bering the great stream of migration that pours through the islands every 

 spring and antumn, it is difficult to believe in the possibility of even an 

 insular race being developed ; indeed, we might as well expect to find a 

 race similar to that in the south-west of Norway, which has been separated 

 by Dr. Stejneger as T. bergensis, though all Scandinavian ornithologists 

 do not acknowledge the validity of the species. Mr. Seebohm states the 

 average size of the eggs of the Faroe Wren to be greater than those of the 

 typical form ; this is probably the case, but the one example given is to me 

 hardly conclusive, for I have weighed some hundreds of eggs of many 

 different species, and have found great differences between the weights of 

 sets of eggs laid by individuals belonging to the same species. — Harold 

 Raeburn (Romford, Essex). 



Dispersal of Oak Trees by Wild Ducks. — Walking through Holkham 

 Park on the 1st of June this year, my companions and I observed that 

 hundreds of acres of grass-land were studded with seedling oaks, two to three 

 inches high, and on areas where no oak trees are growing. I can only 

 account for this abnormal dispersion of seedling oaks through the agency of 

 Wild Ducks, Anas boschas. During the severe winter of 1890 — 91 the 

 lake in Holkham Park was frozen over for six weeks, aud the thousands of 

 Mallard that make it their winter home were driven to the woods, where 

 they spent the day, particularly under the oak trees, searching for food ; 

 immense flocks, so tame that a person might approach them within a few 

 yards, were constantly engaged feeding on the fallen acorns, and I spent 

 many hours last winter watching them. After feeding, the Ducks spread 

 themselves over the park, and I presume the undigested acorns must have 



