88 



TROPICAL WILD LIFE IN BRITISH GUIANA 



(Groups foiiud tyj^ically in more than one Zone) 



Ground Low Jungle Mid Jungle Tree-tops 



(0-20 feet) (20-70 feet) (70-200 feet) 



Goatsuckers Goatsuckers Hummingbirds Flycatchers 



Hunimingbirds Flycatchers Hunmiingbirds 

 Tanagers Tanagers 



INIammals permit a similar mode of representation of 

 altitudinal distribution : 



Opossums Anteaters 

 Sloths 

 Bats 

 Coatis 

 Squirrels 

 jNIarmosets 

 Kinkajous 



Anteaters 



Armadillos 



Tapirs 



Peccaries 



Deer 



Cats 



Dogs 



Galictis 



Rodents 



Red Howlers 

 Beesa JNIonkeys 



Returning to the birds of the jungle. Accepting 1 to 

 10 as the gradation of light from the dimmest part of the 

 jungle to full sunlight, and with the same divisions as a 

 basis, we can form an interesting table of relative percent- 

 ages of dull and brilliant birds: 



Gradation 



ofLio-ht ^^^ THREE FIVE TEN 



Percentage 



of Bright 



Birds 8 50 83 



This by no means indicates that all the brilliant birds 

 are conspicuous in their native haunts or that the dull ones 

 are correspondingly protected by their pigment. A quad- 

 rille wren hopping about and filling the low jungle with its 

 wonderful unearthly melody, is a most conspicuous bit of 

 life in spite of its garb of brown and buff. A parrakeet 

 with spots of yellow on vivid green, opalescent in the hand, 

 is but one leaf among a million in the tree-tops. 



