John P Trinkaus' MBL Embryology Course Notes, Notebook I, 1939. Page 78

Notes from Oscar Schotte's lecture. Trinkaus continues his notes from the previous page on the cleavage of the sea urchin embryo with information about the 5th (with diagram) and 6th stages of cleavageLecturer: O. Schotte, Lecture "Development of the Echinoderm egg according to Horstadius" (Information taken from the 1939 Embryology Course Book)Page 78 of 113 from the first notebook of lecture and laboratory notes that John P. Trinkaus took during his time as a student in the Marine Biological Laboratory Embryology Course in 1939 in Woods Hole, MANote