MONSTROSITIES 



299 



limb is not a little arbitrary \ I read M. Guinard's Precis after I 

 had been long contemplating the possibly fictitious archetypal 

 hand and foot which characterise so many animals. 



If by archetypal we only mean a type of animals with five 

 digits which is very ancient, then the term is admissible enough, for 



FIG. 92. (a) Right hand of an Ichthyosaur, pi. 23, Book of the Great Sea-Dragons, by 

 Thomas Hawkins ; (b] Right hand of /. Chiropolyostimts, digital portion pi. 7 of same work. 



as low down as the Plesiosaurs, and may be much lower, we already 

 find the five-digited type established. 



Where could this abnormality of sex-digited animals have 

 come from ? Why the five-digited type was so early established 

 we do not know, but we do know that the Ichthyosaurs, which 

 cannot be denied relationship to other vertebrates, had as many as 

 eight digits (Fig. 92 (b] ) ; while /. Chiroligostinus (pi. 3 of Hawkins' 



