410 C. J. Sundevall on the Wings of Birds. 
exception for some of the hinder ones to have a greater 
absolute length than the anterior (e. g. in the Alaudinse, 
Tringarise). It belongs to systematic ornithology to ascertain 
this. If we wish to have an exact determination of their 
length, the unequal forward extension of the cubitus just 
mentioned must be taken into consideration. The best mode 
of comparison is to state the length of the body, and the 
distance from the carpus to the tip of the first arm-feather. 
The cubital feathers are shortest in the Water-birds and 
Waders, especially in those which have the first wing- 
feather the longest. Leaving out of consideration Aptenodytes 
and Alca impennis, in which all the quill-feathers are rudi¬ 
mentary, the foremost arm-feathers extend only half the 
length of the trunk in the Pygopodes generally, although 
the cubitus terminates anteriorly behind the shoulder. In 
Diomedea they do not reach to f; in the Anates (with Anser 
and Cygnus) to about §; in Carbo to f; in Procellaria 
glacialis about to §. In Sterna , on the other hand, they reach 
nearly to the end of the body, and in Larus a little beyond it. 
In the Waders it is a usual character for the anterior 
arm-feathers to reach to about. |-j of the body, as in the 
Tringarise, Charadrinse, and Rallinse. But in the large¬ 
winged forms, Vanellus, Ciconia , Grus , they reach about to 
the root of the tail, and in Ardea somewhat beyond it. 
The Gallinse show the peculiarity that the first feather is 
very short, only §-£ of the following one. The latter 
reaches to §-£ of the trunk, and this applies also to the 
male of Pavo 3 which has the last arm-feathers so remarkably 
elongated. (Of Argus I have no sufficiently perfect speci¬ 
men to examine.) 
In all Raptorial birds the first arm-feather extends con¬ 
siderably beyond the root of the tail, except in Falco , in 
which it about reaches to that point. The arm-feathers 
are longest in the Owls, in which the anterior ones reach 
nearly twice the length of the body (e. g. Strix lapponica 
lj, S. liturata If, S. otus If, Bubo If). In Eagles [and 
Vultures they are usually about If. 
In the Coccyges the first arm-feather is often about even 
