80 ZOOLOGICAL SKETCHES. 



leaves droop, as if the pulsations of Nature's heart had 

 stopped. 



In such moments the traveller who has sought the 

 shade of the caucho forests is often startled by a singular 

 cry in the tree-tops, a long-drawn, tremulous moan, not 

 unlike the wail of the whippoorwill or a certain lugu- 

 brious variation of a watch-dog's yelp. What can it 

 be ? a night-monkey or an owl hooting in broad day- 

 light ? 



" It's a tardo" (black sloth) explains your guide : " he 

 must be somewhere on the south side of that tree. 

 They are very fond of sunshine." 



The tardo (Bradypus tardigradus) has a peculiar talent 

 for making himself invisible. Even a medium-sized 

 tree, without an excessive supplement of tangle-vines, 

 has to be inspected thoroughly and from different points 

 of view before a slight movement in the upper branches 

 attracts your attention to a fluffy-looking clump, not easy 

 to distinguish from the dark-colored clusters of the 

 feather-mistletoe ( Viscum rubruin) which frequents the 

 tree-tops of this mountain-region. Closely-resembling 

 clusters of feathery leaves and feathery hair are often 

 seen side by side on the same branch. Which of them 

 is the animated one ? A load of buckshot may fail to 

 settle the point. I have seen a troop of idle soldiers 

 bombarding a sloth-tree for half an hour with the 

 heaviest available missiles without being able to force 

 the strong-hold of the occupant, who only tightened his 



