78 



In the Stonesfield slate the Stereognathus was found, which Profes- 

 sor Owen believed to have been a placental mammal, hoofed and 

 herbivorous. ■ 



The Cretaceous period is marked by the introduction of the 

 Tileostia, which includes most of our existing fishes, as the cod, 

 salmon, perch. What mammalian forms existed have not yet 

 been found preserved. 



, The Tertiaries are marked by an abundance of mammalian forms, 

 some of which in the Eocene seem to connect the rhinoceros, horse, 

 and tapir. The highest form yet found was the ape, Macacus 

 Eoccenus. 



In the Mieoeene two forms of ape are found, Pliopithecus an- 

 tiquus and Dryopithecus Fontani. In the Pleistocene period we 

 have the remains of man. Here we have noted only the highest 

 forms of each great period of the world's history. That history 

 involves a period of time so immense that the mind utterly fails to 

 grasp it. Thousands of forms appeared, and disappeared never 

 to return again, but the highest of each great period has advanced. 

 The highest forms are the most recent. 



We have seen that the human embryo, from its commencement 

 as a simple cell to its final attainment of the rank of man, passes 

 through a similar course of development. In that course there is 

 one feature totally unlike all human methods of construction. .It 

 is as if a mechanic sat down to make a first-class steam engine ; 

 but instead of planning out the perfect form and constructing it, 

 each part directly formed for its final result, he commenced by 

 making the first engine ever constructed ; then improving it slightly 

 so as to represent the second stage ol the invention, pulling old 

 parts asunder and using up the old materials, vigorously follow- 

 ing the historical course of improvement, omitting no important 

 modification that had ever been made, till the final result was 

 attained. Why is this ? The disbeliever in evolution has no 

 answer. Mr. Darwin, following the course of thought suggested 

 by thinkers who have gone before him, but far outstripping them 

 in the amount of his contribution, suggests the only answer pos- 

 sible. He replies, that the long line of living forms that have sue- 



