284 BIRDS OF NORFOLK. 



stoutest. In measuring their respective beaks along 

 the upper mandible, the thin-bill was the longest by the 

 amount of its projection beyond the lower mandible, but 

 measuring round the base of each beak the thin-billed 

 example was about three-eighths of an inch less than 

 the others. In appearance the thick-billed bird has a 

 decidedly corvine character, whilst the thin-billed 

 more nearly resembles the sturnidce. Whether or 

 not this marked difference in the form of the beak 

 may be considered as establishing a specific differ- 

 ence, the fact of examples of both varieties having 

 occurred in this country renders it, as Mr. Fisher 

 remarks in the "Zoologist" (p. 1074),"^ a subject of 

 considerable interest to the British ornithologist. The 

 figure in Bewick is apparently taken from a thin- 

 billed bird, and that in Yarrell from a thick-billed 

 specimen formerly in his collection, whilst two at least 

 out of the three Norfolk examples have thin bOls, as 

 had also a fourth killed at Wisbech, November 8th, 

 1859, as recorded in the " Zoologist" (p. 6809), by Mr. 

 F. W. Foster, of the Wisbech museum. The question 

 has been raised, however, whether this strange differ- 

 ence in the beaks of our European nutcrackers may not 

 be, as is the case with the Australian Neomorpha 

 gouldi, a sexual and not a specific peculiarity. That 

 singular and very interesting New Zealand species, as 

 figured by Mr. Gould in his *^ Birds of Australia," 

 exhibits even a greater variation in the size and shape 

 of the beak, in different examples, than is found even 

 in the nutcrackers; but the researches of modern 

 naturalists have established beyond a doubt that these 

 birds are but the sexes of one species. " The natives (says 



* " On tlie two British species or varieties of the nutcracker," 

 by W. R. Fisher, with a figure of the RoUesby bird and illustrations, 

 showing the difference in form of the thick and thin beaks, &c. 



