268 



Plate II. Prague Specimen (Young). 1 



This picture shows the bird in a natural position. It lias no 

 white spots in front of its eyes, and no sign of any such spot is 

 shown on the photograph. 



Its upper and lower mandibles both have furrows — upper four 

 distinct, and two obscure furrows ; lower seven distinct furrows. 



The white plumage on this specimen extends up the breast half- 

 way up the throat, and then upwards as a speckled surface as far as 

 to reach the upper portion of the posterior part of the lower man- 

 dible. Where the white plumage approaches the dark upon the 

 throat and upper part of the breast, the dark and white plumage 

 intermingles, which gives the plumage a speckled appearance. 

 There is an extension of the dark plumage on to the white, be- 

 ginning just below the wing. There is a good big patch of oblong 

 shape. 



This figure of the bird might almost lead one to suppose it was 

 some other species than Alca impennis, but assuming it to be cor- 

 rectly named when compared with the Newcastle-upon-Tyne young 

 bird, one would judge as follows : — 



1st, From the absence of the white marks in front of the eyes 

 that it was a younger specimen, as the Newcastle-upon-Tyne speci- 

 men shows clearly the marks in front of the eyes, and the dark 

 plumage upon this spot disappearing. 



2nd, From the furrows upon the mandibles this would be judged 

 to be the older bird, as there are fewer furrows on the upper and 

 under mandibles of the Newcastle-upon-Tyne bird. 



3rd, The plumage of these two specimens upon the heads and 

 breasts is so different that they might be taken as belonging to 

 distinct varieties. The general appearance of the plumage of the 

 Prague specimen would lead one to conclude it was the older bird 

 of the two. 



ith, The Prague specimen has been rather over-stuffed, and would 

 approach closer to the natural bird if the taxidermist had prepared 

 it a little more attenuated in form. It is a most interesting speci- 

 men, and I desire to express my indebtedness to Dr Anton Fritsch, 

 of the Natural History Museum, Prague, for so kindly supplying me 

 with a photograph for this paper. 



1 There is also an adult specimen of Alca impennis Linn, in the Prague 

 Museum. 



