ON VARIETIES IN THE FORM OF ANTHROPOIDS. 213 



differences as of a purely individual character. 

 Much in the description by Alix and Bouvier — as, 

 for instance, their remarks on the comparative 

 smtdlness of the head, on the slenderness and 

 smoothness of the limb bones — appears to me to 

 point to the youthfulness of this Landana specimen. 

 The unlearned may be struck by what is said of 

 the small spinous processes of the upper cervical 

 vertebras in this specimen, but in the common gorilla 

 the processes of the three upper vertebrae are also 

 small (see Fig. 17). Individual and sexual varia- 

 tions in the general development of the cervical 

 spines may be observed, not only in this case, but in 

 the chimpanzee, and even in man. I think it very 

 doubtful whether a characteristic of species can be 

 founded only or chiefly on this distinction. What 

 is said of the colouring of the coat of the so-called 

 new species appears to me still less worthy of con- 

 sideration. I have spoken above in detail of the 

 many individual varieties of the colour of the hair 

 in different specimens of gorillas. I have also 

 observed long, thick hair, not always short, scanty, 

 and worn away, on the backs of many gorillas of 

 different sexes. The condition described by Alix 

 and Bouvier must refer to the hides of aged and 

 sickly animals, or to those younger individuals 

 affected by the kind of mange which is widely 

 diffused in Africa. Every gorilla delights to rub 

 his back against the trunk of a tree, and leans 

 against it in a contented mood, and so also does the 

 chimpanzee. This is the habit of many other mam- 

 mals, such as cats, lions, boars, deer, and elephants. 



