﻿o. OTTOSSON. SOME RARE BIRDS EGGS DESCRIBED. 3 



The eggs were 4 in number in each nest, only one nest 

 contained 5. Almost all the eggs were rather much brooded 

 the llth of June. 



With regard to their appearence they resemble broadly 

 speaking the eggs of Carbo graculus or G. desmaresti, but 

 they are peculiarily enough spotted, which is the first ex- 

 ample, as far as I know, of eggs covered with a chalky coat 

 and at the same time provided with real spöts. These spöts 

 give to the eggs a very stränge aspect. 



The true shell is bluish white, rather smooth with scatter- 

 ed punctiform pores. The shell is, however, provided with 

 a chalky coat of a greyish white colouration, which in most 

 cases completely covers the egg but in some instances leaves 

 greater or smaller parts of the true shell uncovered. Here 

 and there the coat is thickened to form small chalky tuber- 

 osities or broader elevations. 



The pattern is formed partly by dark brown, or liver 

 brown superficial spöts, partly by darker or lighter, ashy 

 grey, or greyish violet spöts deeper in the shell. The spöts 

 are irregular and scattered all över the egg, sometimes they 

 are more roundish and well defined mostly aggregated at the 

 big end. One pgg has a beautiful zone round the broader 

 end. In another the pattern consists of large expanded irre- 

 gular, påle greyish violet spöts situated deep in the shell. 

 In some cases the superficial spöts are dominating, in other 

 the more deeply situated spöts are most prominent. 



As a rule one egg in each set is considerably more 

 spotted than the others, and in some sets there is one un- 

 spotted egg as well. In one clutch all the eggs are un- 

 spotted . 



With regard to their shape the eggs are variable, usually 

 they are lon gish, as a rulestrongly elongated towards the small 

 and (conf. Carbo desmaresti). In some cases the shape is 

 more inflated. 



The size and weight vary in a considerable degree. The 

 two largest eggs measure 61,4 X 38,5 and 59,2 X 39,4 mm. 

 and the two smallest 54, s X 33, s and 52 X 34,6 mm. Medium 

 size: 55,4 X 35,6 mm. 



The greatest weight is 442 ctgm., the smallest weight 263 

 ctgm., average weight 325,9 ctgm. 



I 



