292 THE ZOOLOGIST. 



thinning- out of unarmed ungulate genera and the gradually 

 increasing destructive pressure upon those, whether armed or 

 unarmed, that survived. Their evident loss of calibre since 

 palaeolithic times may be traced chiefly to the coming of man 

 with missile weapons which, in altering the character of the 

 destroying agency, discounted the value of cranial armature in the 

 struggle for life. 





ON THE BEAK OF THE SCOTER. 

 By J. H. Gurney, F.L.S., F.Z.S. 



In the male Scoter, Oidemia nigra (Linn.), the black beak with 

 a yellow patch forms a characteristic feature of the genus and a 

 brilliant contrast of colour ; but this patch is not always of the 

 same size or extent, nor does it invariably occupy the same posi- 

 tion on the upper mandible. This will be seen on reference to 

 the accompanying sketches. Fig. 1 shows the normal appearance 

 of an adult male Scoter, though sometimes the thin line of yellow, 

 which passes over the basal protuberance, does not reach to the 

 forehead. This is its usual appearance in winter, and a bird 

 shot in Caithness in June (now preserved in the Natural History 

 Museum) presents the same appearance, so that the drakes may 

 be presumed to be alike at all times of the year in regard to the 

 colour and shape of the bill. The beak of this bird is correctly 

 delineated in Dresser's * Birds of Europe,' but Yarrell, Gould, 

 and Macgillivray have either figured it incorrectly, or from 

 abnormal examples. Gould's two plates — in his ' Birds of 

 Europe' and * Birds of Great Britain' — are as different as 

 possible from one another, and the colour is of too deep an 

 orange for the normal living example. Neither of them, in fact, 

 is satisfactory. My outline, fig. 1, is merely given for com- 

 parison with the three which follow, and is that of a drake in 

 winter, in the phase familiar to wildfowl-shooters ; but it will be 

 seen how unlike it is to Gould's figure in the * Birds of Great 

 Britain.' 



Figs. 2, 3, and 4 represent abnormal deviations in the distri* 

 bution and extent of colour in the beak of the male Scoter, and 

 are taken from the heads of three examples shot at Brighton* 

 They have all been mounted by Mr. Pratt, of that place, who ten 

 years ago drew my attention to these variations. No. 2 is still in 



