26 A JOURNEY IN BRAZIL. 



he will work out the whole ; and so I believe when the laws 

 of embryological development are better understood, natu- 

 ralists will have a key to the limits of these cycles of growth, 

 and be able to appoint them their natural boundaries even 

 from partial data. 



" Next in importance I would place the Tapirs. This is 

 one of a family whose geological antecedents are verj 

 important and interesting. The Mastodons, the Palasothe- 

 rium, the Dinotheriurn, and other large Mammalia of the 

 Tertiaries, are closely related to the Tapir. The elephant, 

 rhinoceros, and the like, are of the same family. F^om its 

 structural standing next to the elephant, which is placed 

 highest in the group, the embryology of the Tapir would 

 give us a very complete series of changes. It would seem 

 from some of the fossil remains of this family that the 

 Pachyderms were formerly more nearly related to the 

 Ruminants and Rodents than they now are. Therefore it 

 would be well to study the embryology of the Capivari, the 

 Paca, and the Peccary, in connection with that of the Tapir. 

 Lastly, it will be important to learn something of the em- 

 bryology of the Manatee or Sea-Cow of the Amazons. It is 

 something like a porpoise in outline, and seems to be the 

 modern representative of the ancient Dinotheriurn." 



April ~L2th. The lecture to-day was addressed especially 

 to the ornithologists of the party, its object being to show 

 how the same method of study, that of testing the classifi- 

 cation by the phases of growth in the different groups, 

 might be applied to the birds as profitably as to other types. 



"We have made good progress in the last forty-eight hours, 

 and are fast leaving our friends " the trades " behind. The 

 captain promises us smooth waters in a day or two. With 

 the dying away of the wind will come greater heat, but as 



