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THE POPULAR SCIENCE MONTHLY.
things, is of the greatest consequence. The underlying philosophic basis of comparative anatomy and physiology is kept in mind in the selection of the series of types. There is a necessary dependence upon the season for the observation of many of the plants and animals examined; yet the course should never lose its general theme and become a desultory consideration of unrelated forms. Always freeing the descriptions from unnecessary technicalities and Latin names, the more notable facts are presented in such form, that all children may comprehend them. In the