648 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 1908. 



Elephants are rightly accused of timidity and cowardice, though 

 when brought to bay rage may simulate courage, making a charging 

 tusker a most formidable foe. In common with most forest and 

 jungle dwellers, elephants, while relatively dull of sight, are keen 

 of scent and hearing, in fact marvelously so, for, as Schillings tells 

 us, they either have an acuteness of some known sense far beyond our 

 comprehension or possibly some other sense unknown to us. The 

 sentinels of the herd stand Avith uplifted trunk, which emphasizes 

 the value of the sense of smell. 



Elephants rarely breed in captivity, almost all of the tamed indi- 

 viduals having been born wild; hence artificial selective breeding, 

 Avhich has given rise to such valuable results in the betterment of do- 

 mestic animals, is unavailable for the improvement of the race. 



The rate of increase is extremely slow, for Darwin tells us that they 

 begin to bear young at 30 years and continue to do so until 90, during 

 which time six single young are produced on the average. But to 

 illustrate the necessity of a check upon increase among animals, Dar- 

 Avin says that even at this slow rate the offspring of a single pair 

 Avould in five hundred years amount to 15,000,000, provided they all 

 lived to maturity. 



EVIDENCES or EVOLUTION. 



The evidences of evolution are threefold : Structure, as shown by 

 comparative anatomy, ontogeny, or individual development, and 

 phylogeny or racial history. The last, paleontology makes known to 

 us. We may, by comparing the structure of a given form Avith that 

 of other animals, gain an insight into the probable course of modifi- 

 cations which it has undergone in the development of its distinctive 

 features and often a hint, at least, as to its ancestry and relationship, 

 as in the case already mentioned of the Hyracoidea and elephants. 

 Again, the small hind limb and hip bones buried deep within the body 

 of the Avhales and the hip bones alone in the case of the manatee 

 (Sirenia), having no possible function, are indubitable evidence for 

 descent in each case from some land-dwelling quadrupedal type. This 

 has been corroborated in the last instance by the recent finding, in 

 the Eocene of the Egyptian Fayum, of Sirenia with hind limbs. 



Ontogeny. 



Embryology shows us the curious parallelism which exists be- 

 tween the individual's history and that of the race, that of the indi- 

 vidual being in most cases a more or less abridged summary of that 

 of its ancestors. 



I have spoken of the shortening and corresponding increase in 

 height of the elephant's skull to provide the leverage necessary in 



