INTEODUCTION. 13! 



Before proceeding to consider the structure of Birds, it may 

 be well first to cast a backward glance over the route we have 

 come, and to once more take stock of the principal forms to 

 which the reader's attention has been called, as being so many 

 specimens of different groups of Birds. 



Our object, as before said, has been to afford some help to 

 the investigation and memory of the beginner in his attempt to 

 obtain a mental grasp of the whole Class of Birds. For this 

 purpose we have spoken of great groups arranged in a rough 

 and ready, or popular, manner, as " Scratchers" or "Gallinaceous 

 Birds," as " Cooers," as " Swimmers or Natatory Birds," as 

 " Waders or Grrallatorial Birds," and as " Eunners or Cursorial 

 Birds." 



Amongst the many forms to which we have referred since 

 speaking of theEmeu* — the last of our CursorialBirds mentioned 

 — are a certain number which have feet specially modified so as 

 effectually to help them in climbing — two toes being turned one 

 way, the two others being turned the opposite way. Amongst 

 the Birds the feet of which are thus modified, are the Wood- 

 peckers, Wrynecks, Jacamars, Cuckoos, Barbets, Toucans, Tou- 

 racous. Plantain-eaters, Parrots, and Trogons — the last named 

 being specially exceptional in the arrangement of their toes. 

 All these Birds, thus specially fitted for climbing, have been 

 distinguished as " Climbers " or " Scansorial Birds." 



The Birds last noted by us — the Hawks, Palcons, Buzzards, 

 Kites, Eagles, Ospreys, Vultures, and Owls — are all Birds of 

 Prey or Eapine, and they are hence spoken of as "Eaptorial 

 Birds." Those most like the Hawk, the generic name of which 

 we saw was " Acdpiter," are also distinguished by the epithet 

 " Accipitrine." 



Almost all the rest of the Birds we have herein referred to 

 (i. e, all since the Cursorial Birds, which are neither Scansorial 

 nor Eraptorial) are, however different in size, form, or appear- 

 ance, frequently called Perching Birds, Perchers, or Insessores. 

 Prom the name of their commonest species, the Sparrow, 

 " Passer" they have also been called Passerine Birds or " Pas- 

 seres ; " and most of them are still commonly so denominated. 

 They constitute the great majority of the whole class of Birds. 

 On account of their prodigious numbers it was long ago felt 

 necessary to divide their members amongst subordinate but large 



* See ante, p. 67. 



