MONSTROSITIES 



•299 



limb is not a little arbitrary \ I read M. Guinard's Pricis 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 /. Chiropolyosti7ius , 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 abnorm'ality 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 {J}) ) ; while /. Chiroligostinus (pi. 3 of Hawkins' 



