METHODS — PAL^ONTOLOGICAL 



47 



pattern was that of stripes, either longitudinal or transverse 

 and more probably the former. In the second stage these 

 bands break up into spots, which still show the longitudinal 

 arrangement and may be either light on a dark ground, or 

 dark on a light ground. In a third stage the spots may again 

 coalesce into stripes, the course of which is at right angles to 

 that of the original stripes, or the spots may disappear, leaving 

 a uniform body-colour, lighter or white on the belly. These 

 changes of colour-pattern have not proceeded at a uniform 

 rate in the various mammalian groups, or even within the same 

 group, for an all-important factor is the mode of life of the 

 particular animal. In general, it may be said that the scheme 

 of colour is such as to render 



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'&k'^' 



^ 



Fig. (j. — Tdj/inis Icrre.-itris, •> (hiyjs old. 

 Compare with Fig. 137, p. 320. (By 

 permission of W. S. Berridge, London.) 



its possessor inconspicuous, or 

 even invisible, and many a 

 creature that seems to be very 

 conspicuous and striking in a 

 museum case can hardly be 

 seen at all when in its natu- 

 ral surroundings. Thus, Arctic 

 mammals and birds, in their 

 winter dress, are white ; desert 

 animals are tawny or sandy- 

 brown ; forest animals are frequently striped or spotted ; while 

 those that live on open plains are more commonly of uniform 

 colouration. There are exceptions to these rules, but they 

 hold good for the most part. From careful comparative study 

 of the teeth and skeletons a clew may be gained as to the 

 habits of animals and from the habits something may be 

 inferred as to the colouration. 



It would, however, be misleading to claim a greater au- 

 thority for these attempts at restoring a long-vanished life 

 than can fairly be ascribed to them. The general form and 

 proportions of the head, neck, body, tail, limbs and feet may be 

 deduced with a high degree of accuracy from the skeleton, 



