104 TROPICAL NATURE, AND OTHER ESSAYS. 



fissirostral and scansorial groups of the older naturalists. 

 They may be described as, for the most part, arboreal 

 birds, of a low grade of organization, with weak or 

 abnormally developed feet, and usually less active than 

 the true Passeres or perching birds, of which our 

 warblers, finches, and crows may be taken as the types. 

 The order Picarise comprises twenty-five families, some 

 of which are very extensive. All are either wholly or 

 mainly tropical, only two of the families — the wood- 

 peckers and the kingfishers — having a few representa- 

 tives which are permanent residents in the temperate 

 regions ; while our summer visitor, the cuckoo, is the 

 sole example in Northern Europe of one of the most 

 abundant and widespread tropical families of birds. 

 Only four of the families have a general distribution 

 over all the warmer countries of the globe — ^the cuckoos, 

 the kingfishers, the swifts, and the goatsuckers ; while 

 two others — the trogons and the woodpeckers — are only 

 wanting in the Australian region, ceasing suddenly at 

 Borneo and Celebes respectively. 



Cuckoos. — Whether we consider their wide range, 

 their abundance in genera and species, or the pecu- 

 liarities of their organization, the cuckoos may be taken 

 as the most typical examples of this extensive order of 

 birds ; and there is perhaps no part of the tropics where 

 they do not form a prominent feature in the ornithology 

 of the country. Their chief food consists of soft insects, 

 such as caterpillars, grasshoppers, and the defenceless 

 stick- and leaf- insects ; and in search after these they 

 frequent the bushes and lower parts of the forest, and 

 the more open tree-clad plains. They vary greatly in 

 size and appearance, from the small and beautifully 



