PHYSIOPHILOSOPHICAL SYSTEMS.

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of Pander 1 upon the development of the chicken in theegg, which have opened the series of those truly originalresearches in Embryology of which Germany may justlybe proud, were made under the direction and with thecooperation of Dollinger, and were soon followed by themore extensive works of Eathke and Baer, whom the civi-lized world acknowledges as the founders of modern Em­ bryology .

The principles of classification propounded by K. E. von Baer seem never to have been noticed by systematicwriters ; and yet they not only deserve the most carefulconsideration, but it may fairly be said that no naturalist,besides Cuvier , has exhibited so deep an insight into thetrue character of a natural system, supported by such anextensive acquaintance with the subject, as this greatembryologist has in his “ Scholien und Corallarien zu derEntwickelungsgeschichte des Huhnchens in Eie .” 2 Theseprinciples are presented in the form of general proportionsrather than in the shape of a diagram with definite syste-matic names; and this may explain the neglect which ithas experienced on the part of those who are better satis-fied with words than with thoughts. A few abstracts,however, may show how richly the perusal of his work islikely to reward the reader.

The results at which K. E. von Baer had arrived by hisembryological investigations, respecting the fundamentalrelations existing among animals, differed considerablyfrom the ideas then prevailing. In order, therefore, to becorrectly understood, he begins, with his accustomed ac-

1 Pander, Beitrage zur Entwicke- flexion von Dr. Karl Ernst von Baer ;lungsgeschichte des Huhnchens im Konigsberg, 1828,4to.—See also ActaEie; Wurzburg , 1817, 1 vol. fol. Nova Acad. Leop. Csesar, vol. 13, and

2 Ueber Entwickelungsgeschichte Meckel’s Arch., 1826.der Thiere, Beobachtung und Re-