122 THE BIRDS OF BRITISH GUIANA. 



known, had not before been recorded as resident in the 

 locality. 



Of our peculiar families, I need only mention such as the 

 Sugar-Creepers, the Greenlets, the Mannikins, the Cotingas, 

 the Trogons, the Toucans, the Barbets, the Hoatzin, the Tina- 

 mous, the Curassows, and other equally restricted tropical 

 American forms ; while others, such as the Tanagers, the 

 Tree-Creepers, the Ant-Thrushes, the Tyrant-Shrikes, the 

 Humming-birds, the Hang-nests and other such forms, which, 

 though they range into the temperate parts, yet are enor- 

 mously abundant in the tropics, will occur at once to your 

 minds. It is worth noting in this connection that many of 

 those families, such as the Crows, Starlings, true Shrikes, and 

 true Creepers, which give so many characteristic types to 

 the Northern regions and to the Old World, are almost, if 

 not entirely, absent from the American tropics. 



A noteworthy characteristic of our birds also is the very 

 marked abundance of the individuals of a species. This no 

 doubt is due to the protection afforded them by the abun- 

 dance of trees in the forests and bushy plains, and to the 

 enormous quantity of food in the form of seeds, fruits and 

 insects, with rapid multiplication in an almost uniform and 

 favoring temperature. Very many forms are only to be 

 met with in well-defined districts ; thus, the species of such 

 genera as Cotinga, Xi/>hoIena, Phxnicocercus, Gyninocephalus, 

 Gymnodcrus, are only encountered in densely forested 

 localities ; Rupicola only in the hills ; Fluvicola, Pitangus, 

 Arundinicola, Quiscalus only in open places and along the 

 river sides ; while others, such as Troglodytes and Cassicus, 

 are most abundant in cleared places or in the neighborhood 

 of the habitations of man. 



The food relations of many of our birds are also peculiar. 

 A very considerable number of our Hawks, examined at 

 different times of the year, and in different places, have re- 

 vealed only a diet of moths, beetles, grasshoppers, locusts, 

 leaves and fruit. While just as certainly the genus Herpe- 



