PRESENTATION OF THE PALEOZOIC 379 



how, in their opinion, the Paleozoic should be presented to students in 

 a first year course. The answers arc interesting and are worthy of the 

 careful consideration of those who teach this subject. Two of these 

 teachers were of the opinion that the discussion of the animals and plants 

 of the Paleozoic should be by periods rather than by eras — that is, the 

 life of the Paleozoic should be treated from the stratigraphic rather than 

 from the biologic point of view. They believe the subject has, on the 

 whole, been properly presented ever since geology became a science. As 

 one says: "Doubtless a student would get a better idea of the animal or 

 plant groups by having each discussed as a unit, but he would fail to 

 grasp the geological significance of the group." Two of the eight teach- 

 ers favored grouping together the life under two divisions, the late and 

 early Paleozoic, perhaps under such heads as Eo-Paleozoic and Neo- 

 Paleozoic. This they considered desirable because for beginners there is 

 hardly enough difference between the Cambrian and Ordovician faunas, 

 for example, to make it worth while to point out distinctions. On the 

 other hand, the changes between the Cambrian and Permian are rather 

 too great to go unnoticed until the end of the discussion of the Paleozoic 

 era. Four advocated the gathering together of the life of the Paleozoic 

 in one place and the physical history in another. There is much to be 

 said for this last suggestion, but the danger of losing the geological sig- 

 nificance of the group is great. Moreover, with this presentation the 

 student might become confused because of the large number of periods 

 which would necessarily be discussed with each class of animal or plant. 



Suggested Methods of Teaching 

 classification of the periods 



All things considered, it seems desirable to change our method of pre- 

 senting the material for the study of this difficult era, and my belief at 

 present is that beginning students would have less trouble and would 

 learn more of value if the animals and plants were grouped together 

 under earlier, or Eo-Paleozoic, and later, or Neo-Paleozoic. If this were 

 done, much repetition could be avoided and the descriptions and classifi- 

 cation of Paleozoic plants and animals could be made much easier and 

 more interesting, while time would be left for the acquiring of a knowl- 

 edge of the subjects mentioned a few minutes ago. 



RELATIVE EMPHASIS TO BE PLACED ON THE STUDY OF VERTEBRATES 

 AND INVERTEBRATES 



There is an interesting inconsistency in the argument that the inver- 

 tebrates of the Paleozoic should be discussed by periods, and that much 



