102 TROPICAL NATUKE, AND OTHEU ESSAYS. 



witli tlie Malay islands as far as Java and Borneo, is 

 also very poor, witli about thirty species. Tropical Ame- 

 rica is very much richer, possessing about 140 species, 

 among which are many of the largest and most beautiful 

 forms. But of all parts of the globe the tropical islands 

 belonging to the Australian region (from Celebes east- 

 ward), together with the tropical parts of Australia, are 

 richest in the parrot tribe, possessing about 150 species, 

 among which are many of the most remarkable and 

 beautiful of the entire group. The whole Australian 

 region, whose extreme limits may be defined by Celebes, 

 the Marquesas, and the New Zealand group, possesses 

 about 200 species of parrots. 



Pigeons. — These are such common birds in all tem- 

 perate countries, that it may surprise many readers to 

 learn that they are nevertheless a characteristic tropical 

 group. That such is the case, however, will be evident 

 from the fact that only sixteen species are known from 

 the whole of the temperate parts of Europe, Asia, and 

 North America, while about 330 species inhabit the 

 tropics. Again, the great majority of the species are 

 found congregated in the equatorial zone, whence they 

 diminish gradually toward the limits of the tropics, and 

 then suddenly fall off in the temperate zones. Yet 

 although they are pre-eminently tropical or even equa- 

 torial as a group, they are not, from our present point 

 of view, of much importance, because they are so shy 

 and so generally inconspicuous that in most parts of the 

 tropics an ordinary observer might hardly be aware of 

 their existence. The remark applies especially to 

 America and Africa, where they are neither very 

 abundant nor peculiar ; but in the Eastern hemisphere, 



