102 



THE KINGDOM OF MAN 



ultimately connected by very simple, remote, and not 

 by proximate ancestors, with one another and with the 

 ancestors of vertebrates. 



The origin of the limbs of vertebrates is now gener- 

 ally agreed to be correctly indicated in the Thatcher- 



FlG. 21. 



The unicellular parasite ?Benedenia, from the gut of the common 

 Poulp or Octopus. i,---is'ithe normal male individual; 2 and 3 show 

 stages in the production of spermatozoa on its surface by budding ; 

 4, 5 and 6 show a female parasite with spermatozoa approaching it : 



FIG. 22. 



Production of spermatozoa on the surface of the unicellular parasite 

 Coccidium oviforme, from the Rabbit's intestines. 



