THE HISTORY OF THE PROTOPLASMIC THEORY 9 



into later, being only incidentally n&ntioned here and there in 

 the following account of our present knowledge of the nature of 

 the elementary organism. 



The enormous amount of knowledge which has been acquired 

 through a century of investigation will be best systematically 

 arranged in the following manner : 



In the first section the ch em ico -physical and morphological 

 properties of the cell will be described. 



The second section will treat of the vital properties of the cell. 

 These are, (1) its contractility, (2) its irritability, (3) the phe- 

 nomena of metabolism, (4) its power of reproduction. 



Further, in order to complete and amplify our account of the 

 nature of the cell, two sections more speculative in character will 

 be added, one treating of the relationship between the proto- 

 plasm, the nucleus, and the cell products, and the other of the 

 cell considered as the germ of an organism. 



Literature I. 



1. FB. AENOLD. Lehrbuch der Physioloyie des Mensclien. 2 Theil. Zurich. 



1842. Handbuch der Anatomie des Mensclien. 1845. 



2. DE BABY. Myxomyceten. Zeitschrift f. wissenschaftl. Zool. 1859. 



3. LIONEL S. BEALB. On the Structure of the Simple Tissues of the Human 



Body. 1861. 



4. BISCHOFF. EntwicJclungs-geschichte des Kanincheneies. 1842. 



5. B. BBOWN. Observations on the Organs and Mode of Fecundation in Orchidece 



and Asclepiadece. Transactions of the Linnean Soc. t London. 1833. 



6. BBUCKE. Die Elementarorganismen. Wiener Sitzungsber. Jahrg. 1861. 



XLIV. 2. Abth. 

 CLELAND. On Cell Theories. Quar. Jour. Microsc. Sc. XIII., p. 255. 



7. COHN. Nachtrage z. Naturgeschichte des Protococcus pluviatilis. Nova acta. 



Vol. XXIL, pp. 607-764. 



8. BONAVENTUBA CoBTi. Observazioni microsc. sulla Tremella e sulla circola- 



zione delfluido in una pianta acquaiola. 1774. 



DALLINOER and DBYSDALE. Researches on the Life History of the Monads. 

 Month. Mic. Journ. Vols. X.-XIII. 



9. GBEW. The Anatomy of Plants. 



10. HAECKEL. Die Radiolarien. 1862. Die Moneren. 



11. HENLE. Symbols ad anatomiam villorum intestit.alium. 1837. 



12. OSCAB HEBTWIG. Die Geschichte der Zellentheorie. Deutsche Rundschau. 



13. HUXLEY. On the Cell Theory. Monthly Journal. 1853. 



14. KOLLIKEB.- Die Lehre von der thierischen Zelle. Schleiden u. Nageli 



Wissenschaftl. Boianik. Heft 2, 1845. 

 KOLLIKEB. Manual of Human Histology, trans. Sydenham Society. 1853. 



