52 THE EIDDLE OF THE UNIVEESE. 



As the apes approach nearest to man of all the 

 mammals in point of structure, we shall expect to 

 hear the same of their vital functions ; and that we 

 find to be the case. Everybody knows how closely 

 the habits, the movements, the sense-activity, the 

 mental life, and the parental customs of apes resemble 

 those of man. Scientific physiology proves the same 

 significant resemblance in other less familiar processes, 

 particularly in the working of the heart, the division 

 of the breasts, and the sexual life. In the latter 

 connection it is especially noteworthy that the mature 

 females of many kinds of apes suffer a periodical 

 discharge of blood from the womb, which corresponds 

 to the menstruation of the human female. The secre- 

 tion of the milk in the glands and the suctorial process 

 also take place in the female ape in precisely the same 

 fashion as in women. 



Finally, it is of especial interest that the speech of 

 apes seems on physiological comparison to be a stage 

 in the formation of articulate human speech. Among 

 living apes there is an Indian species which is musical ; 

 the hylobates syndactyly,* sings a full octave in perfectly 

 pure, harmonious half-tones. No impartial philologist 

 can hesitate any longer to admit that our elaborate 

 rational language has been slowly and gradually deve- 

 loped out of the imperfect speech of our Pliocene 

 simian ancestors. 



