113 



Length 12 inches, 



The rock pigeons have two broods in the year, and 

 they lay their eggs in nests formed in holes of rocks 

 and ruined towers. 



The columba cenas, or stock-dove, is generally supposed 

 to be the species from whence the innumerable varieties of 

 domestic pigeons have sprung ; but the livia is undoubtedly 

 their origin. Mr. White in his History of Selborne, ob- 

 serves that " the stock-dove is larger than the common 

 house-dove, against the usual rule of domestication, which 

 generally enlarges the breed. Again, those two remarkable 

 black spots on the remiges of each wing of the stock-dove, 

 which are so characteristic of the species, would not, one 

 should think, be totally lost by its being reclaimed ; but 

 would often break out among its descendants/' ^See Wit- 

 loughby's Ornithology, and More's Columbarium) 



ORDER V. GALLING. 



The bill is convex ; the upper mandible arched ; 

 the toes are connected by a membrane at the bottom ; 

 tail-feathers more than 12. 



Birds of this order are furnished with a thick muscular 

 stomach called a gizzard ; which grinds down by its action 

 the seeds of plants such as peas, beans, &c. before the 

 gastric juice can act upon them, so powerful is its effects, 

 that Spallangani found glass spheres, angular pieces of 

 glass, needles, and even sharp lancets fixed in leaden balls 

 broken to pieces, or pulverized. 



