CONCERNING EGGS 55 



the expression is not altogether a correct one, for 

 not all eggs are of that form. The ova of the female 

 thorn moth, for instance, are rectangular in shape, 

 and, when laid, are arranged side by side like a row 

 of bricks ; whilst those of the stick-insects resemble 

 miniature flasks with a small lid at the top. It 

 is true that the majority of birds' eggs are of an 

 oval form, but those of the guillemots and other 

 members of the auk family prove an exception to 

 the general rule and are cone-shaped, the one end 

 being considerably larger than the other. As these 

 are deposited by the birds upon the ledges of high 

 precipitous cliffs without any nest being made, 

 their unusual form serves a very useful purpose, 

 for should they accidentally be disturbed by the 

 movements of their owners, or by the force of the 

 wind, they pivot round and round in a circle upon 

 their apexes, instead of rolling in a more or less 

 straight line which, in all probability, would result 

 in their falling from their resting places and being 

 broken to atoms. Guillemot eggs are very remark- 

 able for their varied tints and markings, and, to 

 quote the writings of Mr. Seebohm, * ... the 

 ground-colours are cream, white, blue, and yellowish- 

 green, dark and clear pea-green, and reddish and 

 purplish brown, with every conceivable inter- 

 mediate tint. Some are irregularly blotched, others 

 are fantastically streaked with browns, pinks, or 

 greys in endless variety, whilst a few are spotless 

 or nearly so.' 



By far the most beautiful of all eggs are those 

 laid by birds, many of them being very prettily 



