CHAPTER 11.

Start on journey to Segovia.--Rocky mountain road.--A poor lodging. --The rock of Cuapo.--The use of large beaks in some birds. --Comoapa.--A native doctor.--Vultures.--Flight of birds that soar. --Natives live from generation to generation on the same spot.--Do not give distinctive names to the rivers.--Caribs barter guns and iron pots for dogs.--The hairless dogs of tropical America. --Difference between artificial and natural selection.--The cause of sterility between allied species considered.--The disadvantages of a covering of hair to a domesticated animal in a tropical country.