THE JACAMARS 1723 



are, moreover, instances to the contrary, as in the case of pigeons, which lay two 

 white eggs in an open nest, while humming birds, which are also Picarian, likewise 

 build an open nest and lay white or light-colored eggs. No definite rule can be laid 

 down as to the nesting of the Picarians, and there are further exceptions, though 

 of a modified kind, and capable of a different explanation, such as occur in the case 

 of the cuckoos, some of which lay white eggs, and others variegated and colored 

 ones. Although in addition to the above not very important features, there are 

 certain osteological characteristics peculiar to the Picarians, such as the form of the 

 upper arm bone or humerus, which exhibits well-marked differences from the cor- 

 responding bone of the perching birds, the definition of the order by means of well- 

 marked and exclusive features is by no means easy. The palate is sometimes of 

 the so-called aegithognathous type, and at others of the bridged or desmognathous 

 form; while the structure of the foot is variable in every degree, some Picarians 

 having a foot in which the fourth toe is directed backward, while in others the foot 

 has the front toes joined together, so as to form a very flat perching surface. The 

 Picarians may be divided into three chief sections, which may be called Scansores, 

 or climbing Picarians; Coccyges, or cuckoo-like Picarians, and- Coraciiformes, or 

 roller-like Picarians; the chief differences between these groups occurring in the 

 arrangement of the tendons of the feet, which need not be explained in a work of 

 the present nature. 



THE JACAMARS 

 Family GALBULID^& 



Commencing with the climbing section of the order, our first representatives 

 are the South- American jacamars, of which about twenty species are known. All 

 these birds have the so-called zygodactyle type of foot, in which the fourth toe is 

 directed backward parallel to the first. The bill is peculiarly long and straight; 

 there is an aftershaft to the body feathers, which does not occur in the allied group 

 of the puff birds; and there are some further differences in the arrangement of the 

 feathers of the under surface, the tract on the breast having a branch on the throat. 

 The number of tail feathers varies in a somewhat peculiar manner, the normal num- 

 ber being twelve, but in two genera out of the six (Brachygalba and Jacamaralcyon) 

 the outer feather on each side is wanting, thus reducing the number of feathers to 

 ten. Although nothing absolutely decisive is known as to the breeding habits of 

 the jacamars, it is stated that in Tobago they build in holes in mud banks, like the 

 motmots, and lay pure white and nearly spherical eggs; while the three- toed 

 Brazilian jacamar has been seen boring holes in banks as if for the purpose of 

 nesting. 



Together with four other genera of the family, the true jacamars 



. constitute a subfamily group; Galbula and the allied genus Urogalba 



having the middle pair of tail feathers elongated, while in the others 



the tail is short and squared; the three-toed jacamars (Brackygalba) being notable 



for the feature from which they take their name. In these jacamars the prevailing 



