GREEN COLOUR OF SLOTH 



covering of long and coarse hair : secondly, the im- 

 mensely long and hooked claws, which are two in the 

 fore limbs in the case of the two- toed sloth, Choice pus, 

 and three in Brady pus. 



It has no fingers to crook to retain its hold upon a 

 branch ; nature has already hooked them for it in a per- 

 manent fashion. It can only clutch. The long, wiry 

 hair droops over its body, and forms an excellent shelter 

 against a tropical downpour. As to this hair, it has been 

 pointed out that it fadges well with the sloth's habits. 

 Instead of lying in different directions in different regions 

 of the body, as is so generally the case with the mam- 

 malia, the hair " flows " only downwards ; it cannot 

 therefore get wet. But a third danger remains besides 

 the chance of falling, and of getting a soaking. The 

 sloth has tender flesh, and is an appetizing morsel to 

 tree-frequenting beasts of prey ; and South America 

 harbours one of the largest of these, to wit, the jaguar. 

 Defenceless as the sloth is against such attacks, nature 

 has provided it with the means of apparently circum- 

 venting probable foes. It will very possibly be noticed 

 in examining carefully the hair of the sloth, that this has 

 often a distinctly green colour. Now it was ascertained 

 a good many years ago that this green colour was not in 

 the least due to an actual green colour of the individual 

 hairs, but to the presence within them of minute green 

 plants similar to those which colour so vividly the 

 weather side of trees, to microscopic algse in fact. This 

 gives to the pelage of our sloth a not unstriking likeness 

 to lichens, which is borne out by its bunched-up body, 

 not unlike a tree stump. There is, in fact, in one sloth at 

 least there are several species of sloth a mark in the 

 middle of the back which suggests a broken end of a 

 branch. Thus we see that the wind is tempered to the 

 shorn lamb, if, indeed, so very shaggy a creature may 

 be used as an illustration of this dictum. 



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