86 EXPL-LXATIOX OF THE TLAIFS. 



hundred and ninety-eight spotted eggs, ninety-nine are most 

 marked at the large end, only six most spotted at the small 

 end, and ninety-three indiiferently marked all over, or at least 

 not more at one end than the other. 



It is satisfactory to note, in conclusion, that Dr. Thieneman 

 attributes the markings on eggs to escapes of blood from the ves- 

 sels of the oviduct, and states further that both the shell and the 

 spots are produced by inflammatoiy processes caused by the pres- 

 sure of the passing egg. His figures corroborate what has been 

 advanced with regard to the large end being much more com- 

 monly and more strongly marked than any other part of the egg. 



Kead November 23rd, 1876. 



The following Plates are printed from Photographs taken by 

 Mr. J. W. Swan from specimens of eggs in the collection of Mr. 

 John Hancock. To both these gentlemen my best thanks are 

 due for their kind assistance. 



The eggs are represented somewhat less than the natural size. 



EXPLANATION OF THE PLATES. 



PLATE I. 



Fig. 1 . Oval Egg of Arctic Tcni, Sterna paradisea, Bniuuich, showing a 

 broad band or zone of dark colonr covering the broadest part of 

 the egg, leaving both apices clear, or nearly so. Towards the small 

 end the hand sends ofT projections, which taper to point."*, and 

 their direction is from left to right. 



Fig. *-'. Pyriform Egg of Common Snipe, GaUinayo Scohpacimis, Bp., 

 showing a dark cap covering the apex of the large end, with a 

 few spots aronnd it, which diminish in number and size the further 

 they arc from it. The small end is nearly free from spots. 



Fig. 3. Oval Egg of Razor Bill, AIca torda, Linn., showing an irregular 

 ring or zone of blotches encircling the apex of the large end, which 

 is almost quite white. A few spots arc seen towards the middle, 

 but the small end of the egg is white. 



Fig. 4. Pyriform Egg of Guillemot. Uria troile, Linn., showing a large 

 dark-coloured cap covering the greater part of the large end. The 



