The winter succeeding the lessons on archæology, Mr. B. H. Van Vleck, who had spent a considerable portion of the previous summer in preparing specimens for this work, gave fifteen lessons on zoölogy. The study of the general morphology of animals was made under advantages such as had never before been offered in this school, and enabled teachers to see and study structures not usually within their reach. The work was mainly directed to the observation and study of a limited number of types, but general points in physiology and anatomy were also taken up in a comparative way. The microscope was also used in this work. This special course was continued during the next two terms.
Dr. J. Walter Fewkes gave a series of ten lessons, during the winter of 1890-'91, on Common Marine Animals from Massachusetts Bay. Special attention was given to the mode of life, differences in external forms, local distribution, habitats, methods and proper times to collect the eggs, young, and adults. The anatomy, embryology, and morphology of the species considered were dealt with incidentally.
J. Walter Fewkes.
"The relative abundance of species and individuals, local causes which influenced distribution, the rocky or sandy nature of the shores and their characteristic faunæ, and the influence of depth of water tides and temperature, were also considered."
The relations and boundaries of the marine fauna of New England were treated of under the following heads: Comparison of the Fauna of Massachusetts Bay with that of Narragansett Bay and the Bay of Fundy, and Causes of the Differences Observed; Pelagic Animals; Littoral and Shallow-Water Genera; Introduced and Indigenous Marine Animals; and Marine Animals which inhabit both Brackish and Fresh Water.
It having been found that for several years the audiences at the general courses had been decreasing, it became evident that the giving of general information had accomplished a mission, but that there was a demand for more specialized courses of study and that a change of policy was warranted. It was therefore determined to abandon the general courses and continue the special prolonged laboratory courses.
Since 1891 all lessons have been given either in the form of laboratory lessons or field work, and the school was organized and conducted upon a new and more effective basis. The teachers have been required to keep notebooks and attend examinations in order to be candidates for the certificates which have been, and will continue to be, granted to those who have completed a series of lessons.
In the fall of 1890 was begun a course of lessons on paleontology which had been planned for some time but had not been previously undertaken because the teachers lacked the knowledge of the elements of zoölogy and geology which was a necessary preparation for those taking up the study of the history of animals as found in the earth's crust. The members of this class, which now began to make systematic observations upon fossils, were found to be sufficiently prepared to study certain groups which illustrated the laws of evolution. The class was limited in number and was under the instruction of Professor Hyatt, who for five years conducted the most advanced course of lessons ever given in The Teachers' School of Science, and such as have not elsewhere been offered to teachers nor to many classes of college students.
The lessons began with general instruction in the use of the microscope, the structure of cells and their union and differentiation into tissues, and then a study of simplest organisms—Protozoa. The work was continued through Porifera, Hydrozoa, and Actinozoa, and the types of fossils compared with their living representatives. The periods of occurrence of fossilized remains in the rocks were noted, and the characteristics of the different periods mentioned, but details of stratigraphic character were subordinated to the tracing out of the relations of the animals and the laws which governed the evolution of their forms. Special attention was given to those classes whose history is most complete and which furnish the best specimens for examination.