EXTRACT XXI. A. 



ON THE STAGES OF EVOLUTION OF THE HUMAN 

 ORGANISM, DIVIDED INTO UNICELLULAR, BLASTO- 

 DERMIC, OR MULTICELLULAR, NEURENTERIC, AND 

 VISCERO-SKELETAL. 



THE sequence of formative events, embraced in the 

 above series, comprises the whole of the evolutionary 

 stages of human organic life, which, when regarded in 

 conjunction with the involutionary stages of that life, 



FIG. 72. FIG. 73. 



M. 



FIG. 72. DIAGRAM OF AN ANIMAL CELL MUCH MAGNIFIED. (E. A. S.) 



/, protoplasm, with vacuoles and granules ; n, nucleus, with intranuclear network 

 and nucleolus ('). 



FIG. 73. STRIATED EPITHELIUM CELL, FROM THE DUCT OF A SALIVARY 

 GLAND ; HIGHLY MAGNIFIED. SEMI-DIAGRAMMATIC. (E. A. S.) 



gr, granular protoplasm ; sir, striae ; , nucleus. 



constitute the whole " span " of its existence. The 

 phenomena embraced in each and every stage of human, 

 in common with all other, life are the outcome of 

 physico-dynamic agency and specific, or vital, formative 

 impulse, embraced in and transmitted from parent, to 



