26 Prof. BucKLAND on the Adaptation of the Structure 



The tame Sloths never willingly remained on the ground, except to pass 

 from one tree to another : all the movements of the animal are slow ; it moves 

 its claws or pincers slowly ; in eating it chews slowly ; it also climbs slowly ; 

 the moisture of the leaves it eats suffices it for drink, without descending to 

 obtain water. None of those kept by Mr. Burchell were ever seen to drink. 

 The full-grown animals M'ere never heard to utter any sound, but the young 

 one occasionally (though rarely) gave a short cry or whistling squeak of a 

 single note. 



They showed no indication of fear, and seemed to give attention only with 

 their eyes ; they took no notice of the boy that carried them often across the 

 garden to their place in the verandah, with their long arms sprawling; tlie 

 only objects of their regard were trees ; they fight on their backs, and grapple 

 their enemy to strangulation. The use of the long wool that covers the 

 body, and even the face, seems to be to guard them from the annoyance of 

 insects. 



The following descriptions in Piso and Marcgraf's Natural History of Brazil, 

 p. 221, are evidently the result of personal observation on the habits of the 

 Sloth, and confirm in every respect the views we have been taking of the 

 structure and habits of this animal. 



" Animal est ignavissimum et ad incessum plane ineptum, in arboribus len- 

 tissime rependo progreditur, ibi habitat, foliis arborum vescens ; nunquam bibit, 

 vocem rarissime edit iiiii, fere ut felis junior : arctissime, quaecunque unguibus 

 apprehendit, tenere potest. Quando scandit, caput elevatum lentissime movendo 

 gestat. Pluviam etiam levem admodum metuit." — " Animal sine dubio vivax. 

 Intestinis omnibus exeraptis adhuc se movebat, et pedes contrahebat ut vivum 

 solet quando pendens ad somnum se componit. A junctura pedis cum tibia tres 

 nervi soliilissimi, ad quemlibet unguem unus intensus tendit, quibus ungues 

 incurvare et validissime se sustentare potest*." 



Does it not follow from the above comparisons of the habits of the Sloth with 

 its form and structure, that so far from being in any respect an imperfectly 

 constructed animal, it is fitted with admirable perfection of mechanism to its 

 unusual habits and peculiar condition of life? It is true, that if rapid loco- 

 motion be an essential attribute of a quadruped, the Sloth will labour under 



* Pis. et Marcgr. Hist. Nat. Bras. p. 221. 



