20, 



A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



Bare portion of tibia over 200 mm., tarsus many times longer than 

 toes Phcenicopteri (Flamingoes) 



Bare portion of tibia (if any) not more than 30 or 40 mm., tarsus (if 

 at all) less than twice as long as toes : 



Anseres (Swans, Geese, and Ducks) 



Order PASSERES. 



This Order consists of the ordinary pereliing birds and contains 

 nearly half of the known species of birds. The Order is divided 

 into several suborders, of which in Europe only the largest, the 

 so-called Oscines (singing birds), is found. 



The numerous families are difficult to define, and the limits 

 of some of them are so far very unsatisfactory. On account of 

 great variation of form, the Order is difficult to diagnose by 

 external characters, Orders of birds being chiefly founded on 

 anatomical structure. The palate is segithognathous ; never 

 more than fifteen cervical vertebra? ; deep plantar tendons free ; 

 ambiens absent ; no basi-pter^'goid processes ; young hatched 

 naked and helpless. 



There are always four toes, first or hallux being directed 

 backwards and not reversible, always jointed at same level as 

 the others. An oil-gland is always present, but it is naked, not 

 tufted. Wing with nine or ten obvious primaries ; tail usually 

 with twelve, in a few genera only with ten, rectrices. Land-birds ; 

 feet never webbed. Cosmopolitan. 



Key to families of Order Passeres. 



J Tarsus posteriorly rounded and divided into scutes Alaudidoe (Larks) 

 I Tarsus posteriorly ridged and not scutellated 2 



1st primary rudimentary and hidden ; outermost obvious primary 

 more than half as long as next, often longest (" nine primaried " 

 Passeres) 3 



1st primary obvious, though sometimes small (" ten-primaried " 

 Passeres) 5 



(Longest primary more than twice as long as secondaries : 

 Hirundinidce (Swallows) 

 Longest primary less than twice as long as secondaries 4 



