CHAPTER XIII 



THE PAST HISTORY OF ANIMALS 



I. The two Records — 2. Imperfection of the Geological Record — 

 3. Paleeontological Series — 4. Extinction of Types — 5 . Various 

 Difficulties — 6. Relative Antiquity of Animals 



I. The Two Becords. — Reviewing the development of the 

 chick, W. K. Parker said, "Whilst at work I seemed 

 to myself to have been endeavouring to decipher a palimp- 

 sest, and that not erased and written upon just once, but 

 five or six times over. Having erased, as it were, the 

 characters of the culminating type — those of the gaudy, 

 Indian bird — I seemed to be amongst the sombre grouse, 

 and then, towards incubation, the characters of the Sand- 

 Grouse and Hemipod stood out before me. Rubbing these 

 away, in my downward walk, the form of the Tinamou 

 looked me in the face ; then the aberrant Ostrich seemed 

 to be described in large archaic characters ; a little while 

 and these faded into what could just be read off as per- 

 taining to the Sea Turtle ; whilst, underlying the whole, 

 the Fish in its simplest Myxinoid form could be traced 

 in morphological hieroglyphics." 



There is another palimpsest — the geological record 

 written in the rocks. For beneath the forms which dis- 

 appeared, as it were, yesterday, — the Dodo and the Solitaire, 

 the Moa and the Mammoth, the Cave Lion and the Irish 

 Elk, — there are mammals and birds of old-fashioned type the' 

 like of which no longer live. Beneath these lie the giant 



