Introduction 3 



It had teeth in both jaws of the short blunt beak, a long 

 lizard-like tail with twelve big feathers on each side, 

 wings with both primary and secondary quills, and 

 perhaps a weak keel to the breast-bone. The first two 

 of these points, with other features of the skeleton, 

 distinguish it so sharply from all other birds that it 

 has been placed in a Subclass by itself, termed Archce- 

 ornithes (ancient birds). 



Certain of the latter-day birds have no keel to the 

 breast-bone and therefore no attachment for the flight- 

 muscles — for instance Ostriches, Emus, and Cassowaries; 

 these have been separated from the others and termed 

 Eatitce, as opposed to forms vdth. more or less of a keel, 

 which are known as Carinatce, the latter including all 

 our British species, as will be seen below. 



We cannot here deal with osteology or anatomy, 

 but the subjoined figure will explain the technical 

 terms used for the feathers on different parts of a 

 bird by scientific writers. They do not grow on all 

 parts of the body alike, but on certain tracts called 

 pterylce, while the unfeathered parts are named apteria. 

 It may be of interest to our readers to learn that the 

 sprouting feather consists of a " barrel " or quill which 

 bears, a tuft of rays called barbs, and that these again by 

 splitting ordinarily produce " barbules." The earliest 

 and softest feathers are those which are collectively 

 called " down," while below each down-feather is 

 formed a contour or webbed feather, so that eventually 

 the latter protrudes with the former at its tip. Sub- 

 sequently this falls off, as may easily be observed in 

 the young of any down-clad species. Many nestlings, 

 however, have little or no down at all ; on the other 

 hand many down-feathers remain continually in their 



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