  Allee, W. C. 1916. Chemical control of rheotaxis in Asellus. Jour. Exp. ZoÖl., Vol. 21, pp. 163-198. Amici, 1818. Mem. della Soc. Ital. delle Scienze in Modena, Vol. 18, p. 182. Arey, L. B. 1915. The orientation of Amphioxus during locomotion. Journ. Exp. ZoÖl., Vol. 19, pp. 37-44. Awerinzew, S. 1903. BeitrÄge zur Kenntniss der marinen Rhizopoden. Mitteil. d. zoÖl. Stat. Neapel, Vol. 16. Awerinzew, S. 1904. Ueber die Teilung bei Amoeba proteus Pall. ZoÖl. Anz., Vol. 27, pp. 399-400. Awerinzew, S. 1906. Rhizopoda des SÜsswassers. Trav. Soc. Natu. St. Petersbourg, Vol. 36. Awerinzew, S. 1907. BeitrÄge zur Structur des Protoplasma und des Kerns von Amoeba proteus Pall. ZoÖl. Anz., Vol. 32, pp. 45-51. Bancroft, F. W. 1913. Heliotropism, differential sensibility, and galvanotropism in Euglena. Journ. Exp. ZoÖl., Vol. 15, pp. 383-428. Bancroft, W. D. 1914. The theory of colloid chemistry. Jour. Phys. Chem., Vol. 18, pp. 549-558. Bancroft, W. D. 1913. The theory of emulsification. Jour. Phys. Chem., Vol. 17, pp. 501-520. Baranetzky, J. 1876. Influence de la lumiÈre sur les plasmodia des MyxomycÈtes. Mem. Soc. Sc. Nat. Cherbourg, Vol. 19, pp. 321-360. Barrat, J. O. W. 1905. Der Einfluss der Koncentration auf die Chemotaxis. Zeit. all Physiol., Vol. 5, pp. 73-94. Baunacke, W. 1913. Studien zur Frage nach der Statocystenfunktion. Biol. Centr., Vol. 33, pp. 427-452. Bechhold, H. 1905. Structurbildung in Gallerten. Zeit. physik. Chem., Vol. 52, pp. 185-199. Bechhold, H. 1912. Die Kolloide in der Biologie und Medizin. Dresden und Leipzig, 480 pp. Becquerel, 1838. Ann. d. sci. nat., Vol. 9, p. 78. Beer, Th. 1898. Vergleichend-physiologische Studien zur Statocystenfunktion. Arch. ges. Physiol., Vol. 73, pp. 1-41. Bemmelen, J. M. 1898. Die Absorption. Zeit. anorg. Chem., Vol. 18, pp. 14-37. Bernstein, J. 1900. Chemotropische Bewegungen eines Quecksilbertropfens. Arch. ges. Physiol., Vol. 80, pp. 628-637. Bernstein, J. 1901. Die Energie des Muskels als OberflÄchenenergie. Arch. ges. Physiol., Vol. 85, pp. 271-312. Bernstein, J. 1901. Die KrÄfte der Bewegung in der lebenden Substanz. Naturwiss. Rundschau, pp. 1413-1415; 429-432; 441-443. Berthold, G. 1886. Studien Über Protoplasmamechanik. Leipzig. Blohmann, F. 1894. Kleine Mitteilungen Über Protozoen. Biol. Centralbl., Vol. 14, pp. 82-91. Bohn, G. 1909. La naissance de l’intelligence. Paris. Bohn, G. 1909. Les tropismes. Rapport VIme Congr. Internat. Psychol. Geneve, pp. 15. Bohn, G. 1911. Le nouvelle psychologie animale. Paris. pp. 200. Braun, A. 1852. Über die RichtungsverhÄltnisse der SaftstrÖme in den Zellen der Characeen. Berlin. BrÜcke, E. 1864. Untersuchungen Über das Protoplasma und die ContractilitÄt. Sitzungsb. d. Wien. Akad., Vol. 56, pp. 36. v. Buddenbrock, W. 1911. Untersuchungen Über die Schwimmbewegungen und die Statocysten der Gattung Pecten. Sitzungsb. Heidelberger Akad. Wiss., math.-naturw., pp. 24. v. Buddenbrock, W. 1912. Über die Funktion der Statocysten von Branchiomma vesiculosum. Verhandl. naturhist.-med. Vereines, Heidelberg, 1913. Vol. 12, pp. 256-261. Buller, A. H. R. 1900. Contributions to the knowledge of the physiology of the spermatozoa of ferns. Ann. Bot., Vol. 14, pp. 543-582. BÜtschli, O. 1880-1882. Protozoa. Bronn’s Thierreich. Leipzig. BÜtschli, O. 1892. Untersuchungen Über mikroscopische SchaÜme und das Protoplasma. Leipzig. BÜtschli, O. 1892. Bewegungen der Diatomeen. Vhdl. Naturh.-med. Vereins Heidelberg, N. F., Vol. 4, p. 580. Calkins, G. N. 1904. Evidences of a sexual cycle in Amoeba proteus. Archiv. f. Protistenk., Vol. 5, pp. 1-16. Calkins, G. N. 1912. Genera and species of ameba. Trans. 15th Internat. Cong. Hyg. and Demography. Carter, H. J. 1856. Notes on the fresh water infusoria of the Island of Bombay. Ann. and Mag. of Nat. Hist., Vol. 18, pp. 115, 221. Chambers, R., Jr. 1915. Microdissection studies on the physical properties of protoplasm. Lancet-Clinic, pp. 1-8. Chambers, R., Jr. 1917. Microdissection studies. The visible structure of cell protoplasm and death changes. Amer. Jour. Physiol., Vol. 43, pp. 1-13. Child, C. M. 1915. Individuality in organisms. Univ. of Chicago Press. Clowes, G. H. A. 1916. Protoplasmic equilibrium. Jour. Phys. Chem., Vol. 20, pp. 407-451. Clowes, G. H. A. 1916. Antagonistic electrolyte effects in physical and biological systems. Science, Vol. 43, pp. 750-757. Coehn, A. and Barrat. 1905. Über Galvanotaxis vom Standpunkte der physikalischen Chemie. Zeit. allgem. Physiol., Vol. 5, pp. 1-19. Cornetz, V. 1912. Über den Gebrauch des Ausdruckes “tropisch” und Über den Character der Richtungskraft bei Ameisen. Archiv. ges. Physiol., Vol. 147, pp. 215-233. Corti, 1774. Osservazioni microscopiche sulla Tremella e sulla circolazione del fluido in una pianta acquaiola. pp. 127. Lucca. Czapek, F. 1898. Weitere BeitrÄge zur Kenntniss der geotropischen Reizbewegungen. Jahr. Wiss Bot., Vol. 32, pp. 175-308. Dale, H. H. 1901. Galvanotaxis and chemotaxis of ciliate infusoria. Journ. Physiol., Vol. 34, pp. 291-361. Dale, H. H. 1912. The anaphylactic reaction of plain muscle in the guinea pig. Jour. Pharm. Exper. Therap., Vol. 4, pp. 167-223. Davenport, C. B. 1897. Experimental morphology. New York. Davenport, C. B., and Cannon, W. B. 1897. On the determination of the direction and rate of movement of organisms by light. Journ. Physiol., Vol. 21, pp. 22-32. Davenport, C. B., and Lewis, F. T. 1899. Phototaxis of Daphnia. Science, Vol. 9, p. 368. Davenport, C. B., and Perkins, H. 1897. A contribution to the study of geotaxis in the higher animals. Jour. Physiol., Vol. 22, pp. 99-110. Delage, Y. 1887. Sur une fonction nouvelle des otocystes comme organes d’orientation locomotrice. Arch. zoÖl. exper. et gener., Vol. 4. Dellinger; O. P. 1906. Locomotion of amoebae and allied forms. Jour. Exp. ZoÖl., Vol. 13, pp. 337-358. Dellinger, O. P. 1909. The cilium as a key to the structure of contractile protoplasm. Jour. Morphol., Vol. 20, 170-209. Dobell, C. C. 1914. Cytological studies of three species of Amoeba—A. lacertae Hartmann, A. glebae n. sp. and A. fluvialis n. sp. Arch. f. Protistenk., Vol. 34, pp. 139-189. Doflein, F. 1911. Lehrbuch der Protozoenkunde. Jena. Englemann, T. W. 1879. Über Reizung contractilen Protoplasmas durch plÖtzliche Beleuchtung. Arch. ges. Physiol., Vol. 19, pp. 1-7. Ewart, A. J. 1903. Protoplasmic streaming in plants. Oxford. Flemming, W. 1896. Zelle. Anat. Hefte. Ergebn. Vol. 5, pp. 233-328. Freundlich, H. 1909. Kapillarchemie. Leipzig. Gaidukov, N. 1910. Dunkelfeld Beleuchtung und Ultramicroscopie in der Biologie und Medezin. Jena. Gibbs, J. W. 1878. Equilibrium of heterogeneous substances. Trans. Conn. Acad. Arts and Sciences, Vol. 3, pp. 380-400. Gibbs, D. and Dellinger, O. P. 1908. The daily life of Amoeba proteus. Amer. Jour. Psychol., Vol. 19, pp. 230-241. GlÄser, H. 1912. Untersuchungen Über die Teilung einiger AmÖben. Arch. f. Protestenk., Vol. 25, pp. 27-152. Graham, T. 1861. Liquid diffusion applied to analysis. Phil. Trans., Vol. 151, pp. 183-224; 552-600. Greef, R. 1891. Über den Organismus der AmÖben. Biol. Centrl., Vol. II, pp. 599-639. Greely, A. W. 1904. Experiments on the physical structure of the protoplasm of paramecium and its relation to the reactions of the organism to thermal, chemical and electrical stimuli. Biol. Bull., Vol. 7, pp. 3-32. Grosse-Allermann, W. 1909. Studien Über Amoeba terricola Greef. Arch. f. Protistenk., Vol. 17, pp. 203-257. Gruber, K. 1911. Über eigenartige KÖrperformen von Amoeba proteus. Arch. f. Protistenk., Vol. 23, pp. 252-262. Gruber, K. 1912. Biologische und experimentelle Untersuchungen an Amoeba proteus. Arch. f. Protistenk., Vol. 25, pp. 316-376. Hanstein, 1880. Protoplasma. Heidelberg. Harrington, N. R., and Leaming, E. 1900. The reaction of ameba to lights of different colors. Amer. Jour. Physiol., Vol. 3, pp. 9-18. Hartmann, M. 1914. Bemerkungen Über Amoeba lacertae Hartmann, eine Antwort an Clifford Dobell. Arch. f. Protistenk., Vol. 34, pp. 336-339. Hegner, R. W. 1918. Variation and heredity during the vegetative reproduction of Arcella dentata. Proc. Nat. Acad. Sci., Vol. 4, pp. 283-288. Heidenhain, R. 1863. Stud. d. physiol. Inst. Breslau, Vol. 2, p. 60. Heidenhain, M. 1911. Plasma und Zelle. Bardeleben, Handb. der Anat. d. Menschen. Jena. Hertwig, R. 1902. Die Protozoen und die Ze11theorie. Arch. f. Protistenk., Vol. 1. Hirschfeld, L. 1909. Ein Versuch einige Lebenserscheinungen der Amoeben physikalisch-chemisch zuerklÄren. Zeit. f. all. Physiol., Vol. 9, pp. 529. HÖber, R. 1911. Physikalische Chemie der Zelle und der Gewebe. Leipzig. Hofer, B. 1890. Experimentelle Untersuchungen Über den Einfluss des Kerns auf das Protoplasma. Jen. Zeit., Vol. 24, p. 105. Hofmeister, W. 1867. Pflanzenzelle. Holmes, S. J. 1905. The selection of random movements as a factor in phototaxis. Jour. Comp. Neur. and Psychol., Vol. 15, pp. 98-112. HÖrmann, G. 1898. Studien Über die ProtoplasmastrÖmung der Characeen. Jena. Howell, W. H. 1916. Structure of the fibrin gel and theories of gel formation. Amer. Jour. Physiol., Vol. 40, pp. 526-545. Hyman, L. H. 1917. Metabolic gradients in ameba and their relation to the mechanism of ameboid movement. Jour. Exp. ZoÖl., Vol. 24, pp. 55-99. Hyman, L. H. 1918. Bioelectric phenomena. Science, Vol. 48, p. 518. Jennings, H. S. 1899. Studies on reactions to stimuli in unicellular organisms. The mechanism of the motor reactions of paramecium. Amer. Jour. Physiol., Vol. 2, pp. 311-341. Jennings, H. S. 1901. On the significance of the spiral swimming in organisms. Amer. Nat., Vol. 35, 369-378. Jennings, H. S. 1904. Contributions to the study of the behavior of the lower organisms. Washington. Jennings, H. S. 1906. Behavior of the lower organisms. New York. Jensen, P. 1901. Untersuchungen Über protoplasmamechanik. Arch. f. d. ges. Physiol., Vol. 87, pp. 361. Jensen, P. 1902. Die Protoplasmabewegung. Ergeb. d. Physiol., p. 42. Jensen, P. 1905. Zur Theorie der Protoplasmabewegung. Anat. Hefte, Vol. 27, pp. 829-858. Kite, G. L. 1913. Studies on the physical properties of protoplasm. Amer. Jour. Physiol., Vol. 32, pp. 146-165. Klebs, G. 1885. Biol. Centralbl. Vol. 5, p. 353. KÜhne, W. 1864. Untersuchungen Über das Protoplasma und die KontractilitÄt. Leipzig. KÜster, E. 1910. Über VerÄnderungen der PlasmaoberflÄche bei Plasmolyse. Zeit. f. Botan., pp. 689-717. Kusano, S. 1909. Studies on the chemotactic and other related reactions of the swarm spores of myxomycetes. Jour. Coll. Agri., Imp. Univ. Tokyo, Vol. 2. Leduc, S. 1912. Le biologie synthetique. Paris. Lee, F. S. 1894-1895. A study of the sense of equilibrium in fishes. Jour. Physiol., Vol. 17, pp. 192-210. Lehmann, O. 1910. FlÜssige Kristalle. Myelenformen und Muskelkraft. MÜnchen, p. 43. Leidy, J. 1879. The freshwater rhizopods of North America. Washington. Lewis, W. C. M. 1910. Die Absorption in ihrer Beziehung zur Gibbschen Theorie. Zeit. Chemie, Vol. 70, pp. 129. Lillie, R. S. 1906. The relation between contractility and coagulation of the colloids in the ctenophore swimming plate. Amer. Jour. Physiol., Vol. 16, pp. 117-129. Lillie, R. S. 1908. The relation of ions to contractile processes. Amer. Jour. Physiol., Vol. 22, pp. 75-90. Loeb, J. 1900. Comparative physiology of the brain and comparative psychology. New York. Loeb, J. 1906. The dynamics of living matter. New York. Loeb, J. 1918. Forced movements, tropisms and animal conduct. Philadelphia. McClendon, J. F. 1909. Protozoan studies. Jour. Exp. ZoÖl., Vol. 6, pp. 265-283. McClendon, J. F. 1911. Ein Versuch amoeboide Bewegung als Folgeerscheinung wechselnden elektrischen Polarisationszustandes der Plasmahaut zu erklÄren. Arch. f. d. ges. Physiol., Vol. 140, pp. 271-280. Mach, E. 1875. Grundlinien der Lehre von der Bewegungsempfindungen. Leipzig. Mast, S. O. 1910. Light and the behavior of organisms. Mast, S. O., and Root, F. M. 1916. Observations on ameba feeding on rotifers, nematodes and ciliates and their bearing on the surface tension theory. Jour. Exp. ZoÖl., Vol. 21, pp. 33-51. Mathews, A. P. 1916. Physiological chemistry. Sec. Ed. New York. Maxwell, S. S. 1910. Experiments on the functions on the internal ear. Univ. Cal. Publ. Physiol., Vol. 4, pp. 1-4. Michaelis, L. 1909. Dynamik der OberflÄchen. Dresden. Moore, A. R. 1916. The mechanism of orientation in Gonium. Jour. Exp. ZoÖl., Vol. 21, pp. 431-432. MÜller, O. Berichte der Bot. Gesell., p. 169, 1889; p. 70, 1897; p. 445, 1899. NÄgler, K. 1909. Entwicklungsgeschichtliche Studien Über amÖben. Arch. f. Protistenk., Vol. 15, pp. 1-53. NÄgeli, C. 1860. Ortsbewegungen der Pflanzenzellen und ihren Theilen. Beitr. z. wiss. Bot., Vol. 2, pp. 59-108. Oppel, A. 1912. Über aktive Epithelbewegung. Anat. Anz., Vol. 41, pp. 400-409. Ostwald, W. 1909. Grundriss der Kolloidchemie. Dresden. Overton, E. 1907. Ueber den Mechanismus der Resorption und Sekretion. Handbuch Physiol., (Nagel) Vol. 2, pp. 744-898. Pallas, P. S. 1766. Elenchus Zoophytorum. Parks, G. J. 1903. On the thickness of the liquid film formed by condensation at the surface of a solid. Phil. Mag., Vol. 5, P. 517. Pauli, W. 1908. Kolloidchemische Studien an Eiweiss. Kolloid-Zeit., Vol. 3, pp. 2-13. Penard, E. 1902. Faune Rhizopodique du Bassin du Leman. GenÈve. Penard, E. 1904. Quelques nouveaux Rhizopodes d’eau douce. Arch. f. Protistenk., Vol. 3, pp. 391-422. v. Prowazek, S. 1909. Studien zur Biologie der Zellen. Biol. Centralbl., Vol. 19, pp. 291-296. Przibram, H. 1913. Die Kammerprogression der Foraminiferen als Parallele zur Hautungsprogression der Mantiden. Arch. f. Entw.-Mech., Vol. 36, pp. 194-210. PÜtter, A. 1904. Die Flimmerbewegung. Ergebn. d. Physiol. Vol. 2, pp. 1-104. PÜtter, A. 1911. Vergleichende Physiologie. Jena. Quincke, G. 1888. Über periodische Ausbreitung und dadurch hervorgerufene Bewegungserscheinungen. Annal. phys. Chem., Vol. 35, pp. 580-642. Quincke, G. 1903. Die OberflÄchenspannung an der Grenze wÄsseriger KolloidlÖsungen von Verschiedener Koncentration. Annal. Physik, Vol. 10. Reichert, E. T., and Brown, A. P. 1909. The differentiation and specificity of corresponding proteins and other vital substances in relation to biological classification and organic evolution. The crystallography of hemaglobins. Carnegie Institution Press. Washington. Richet, C. 1902. De l’action anaphylactique de certains venins. C. R. Soc. Biol., Vol. 54, pp. 170-172. Richet, C. 1912. L’Anaphylaxie. Paris, 286 pp. Rhumbler, L. 1898. Physikalische Analyse von Lebenserscheinungen der Zelle. Arch. f. Entw.-Mech., Vol. 7, pp. 103-350. Rhumbler, L. 1899. Physikalische Analyse und kÜnstliche Nachahmung des Chemotropismus amÖboider Zellen. Physik. Zeitschr., Vol. 1, pp. 43-47. Rhumbler, L. 1899. Physikalische Analyse von Lebenserscheinungen der Zelle. Arch. f. Entw.-Mech., Vol. 9, pp. 32-62. Rhumbler, L. 1899. Allgemeine Zellmechanik. Ergeb. der Anat., Vol. 8, pp. 543-625. Rhumbler, L. 1902. Die Doppelschalen von Orbitolites und andere Foraminiferen, vom Entwicklungsmechanischen Standpunkt aus betrachtet. Arch. f. Protistenk., Bd. 1, pp. 193-296. Rhumbler, L. 1905. Zur Theorie der OberflÄchenkraft der AmÖben. Zeit. f. wiss. ZoÖl., Vol. 83, pp. 1-52. Rhumbler, L. 1905. Der anomogene OberflÄchenspannung des lebenden Zellleibes. Anat. Hefte, Vol. 27, pp. 861-883. Rhumbler, L. 1910. Die Verschiedenartigen Nahrungsaufnahmen bei AmÖben als Folge Verschiedener KolloidalzustÄnde ihrer OberflÄchen. Arch. f. Entw.-Mech., Vol. 30, pp. 194-223. Rhumbler, L. 1914. Das Protoplasma als physikalisches System. Ergebn. d. Physiol., Vol. 14, pp. 474-617. Robertson, T. B. 1905. An outline of the theory of the genesis of protoplasmic motion and excitation. Trans. Royal Soc. South Australia. Vol. 29, pp. 56. Robertson, T. B. 1909. Remarks on the theory of protoplasmic movement and excitation. Quart. Journ. Exp. Physiol., Vol. 2, p. 303. RÖsel von Rosenhof, A. J. 1755. Insecten-Belustigung, 3 Vols. NÜrnberg. Sachs, J. v. 1865. Physiologie. SchÄfer, E. A. 1910. On McDougall’s theory of muscular contraction. Quart. Journ. Exp. Physiol., Vol. 3, p. 63. Schaeffer, A. A. 1910. Selection of food in Stentor caeruleus (Ehr). Jour. Exp. ZoÖl., Vol. 8, pp. 75-132. Schaeffer, A. A. 1914. Reactions of ameba to light. Science, Vol. 39, p. 474. Schaeffer, A. A. 1916. On the feeding habits of ameba. Jour. Exp. ZoÖl., Vol. 20, pp. 529-584. Schaeffer, A. A. 1916. Concerning the species Amoeba proteus. Science, Vol. 44, pp. 468-469. Schaeffer, A. A. 1916. On the behavior of ameba toward fragments of glass and carbon and other indigestible substances, and toward some very soluble substances. Biol. Bull., Vol. 31, pp. 303-337. Schaeffer, A. A. 1917. On the reactions of ameba to isolated and compound proteins. Jour. Exp. ZoÖl., Vol. 22, pp. 53-86. Schaeffer, A. A. 1917. Choice of food in ameba. Jour. Anim. Behav., Vol. 7, pp. 220-258. Schaeffer, A. A. 1917. Reactions of ameba to light and the effect of light on feeding. Journ. Exp. ZoÖl., Vol. 32, pp. 45-74. Schaeffer, A. A. 1917. On the third layer of protoplasm in ameba. Anat. Rec., Vol. 11, p. 477. Schaeffer, A. A. 1918. Functional inertia in the movement of ameba. Anat. Rec., Vol. 14, p. 93. Schaeffer, A. A. 1918. Three new species of amebas: Amoeba Schardinger, F. 1899. Entwicklungskreis einer Amoeba lobosa, Amoeba gruberi. S.-B. Akad. Berlin, Vol. 2, pp. 31-41. Schaudinn, F. 1895. Über die Teilung von Amoeba binucleata Gruber. S.-B. Ges. Natur. Freunde, Berlin, pp. 130-141. Schultz, E. 1915. Die Hyle des Lebens. Beobachtungen und Experimente an Astrorhiza limicola. Archiv. f. Entw.-Mech., Vol. 41, pp. 215-237. Schulze, F. E. 1875. Rhizopodienstudien. IV. Archiv.. f. Mikros. Anat., Vol. 11. pp. 329-353. Schepatieff, A. 1910. AmÖbenstudien. ZoÖl. Jahrb. Abt. Anat., Vol. 29, pp. 485-526. Sharp, R. G. 1914. Diplodinium ecaudatum with an account of its neuromotor apparatus. Univ. Calif. Publ. ZoÖl., Vol. 13, pp. 43-122. Stahl, E. 1884. Zur Biologie der Myxomyceten. Bot. Ztg., Vol. 40, pp. 146-155, 162-175, 187-191. Statkewitsch, P. 1903. Über die Wirkung der InduktionschlÄge auf einige Ciliata. Le Physiol. Russe, Vol. 3, pp. 41-45. Strasburger, E. 1878. Wirkung des Lichtes und der WÄrme auf SchwÄrmsporen. Jen. Zeit. Naturw., Vol. 551-625. Štolc, A. 1900. Beobachtungen und Versuche Über die Verdauung und Bildung der Kohlenhydrate bei einem amÖbenartigen Organismus. Zeit. f. wiss. ZoÖl., Vol. 68, pp. 625-668. Štolc, A. 1910. Über kernlose Individuen und kernlose Teile von Amoeba proteus. Arch. f. Entw.-Mech., Vol. 29, pp. 152-168. Thompson, D. W. 1917. On growth and form. Cambridge, England. Torrey, H. B. 1907. The method of trial and the tropism hypothesis. Science, Vol. 26, pp. 313-323. Torrey, H. B. and Hays, G. P. 1914. The role of random movements in the orientation of Porcellio scaber to light. Jour. Anim. Behav., Vol. 4, pp. 110-120. v. UexkÜll, J. 1909. Umwelt und Innenwelt der Tiere. Berlin. Ulehla, V. 1911. Ultramikroscopische Studien Über Geisselbewegung. Biol. Central., Vol. 31, pp. 645-654, 657-676, 689-705, 721-731. Vahlkampf, E. BeitrÄge zur Biologie und Entwicklungsgeschichte von Amoeba limax einschliesslich der ZÜchtung auf KÜnstlichem NÄhrboden. Arch. f. Protistenk. Vol. 5, pp. 167-220. Verworn, M. 1889. Psychophysiologische Protistenstudien. Jena. Verworn, M. 1892. Die Bewegung der lebendigen Substanz. Jena. Verworn, M. 1903. Die Biogenhypothese. Jena. Verworn, M. 1909. Allgemeine Physiologie. Jena. Wallich, G. C. 1863. On an undescribed undigenous form of Amoeba. Ann. and Mag. Nat. Hist., Vol. 11, p. 287. Wallich, G. C. 1863. Further observations on an undescribed indigenous Amoeba. Ann. Mag. Nat. Hist., Vol. 11, pp. 365-371. Wherry, W. B. 1913. Studies on the biology of an ameba of the limax group. Arch. f. Protistenk., Vol. 31, pp. 77-94. Willis, H. S. 1916. The influence of the nucleus on the behavior of the ameba. Biol. Bull., Vol. 30, pp. 253-271. Wilson, C. W. 1916. On the life history of a soil ameba. Univ. Calif. Publ. ZoÖl., Vol. 16, pp. 241-292. Wilson, H. V. 1900. Notes on a species of Pelomyxa. Amer. Nat., Vol. 34, pp. Yocom, H. B. 1918. The neuromotor apparatus of Euplotes patella. Univ. Calif. Publ. ZoÖl., Vol. 18, pp. 337-396. Bayliss, W. M. 1915. Principles of General Physiology, London. Craig, C. F. 1911. The parasitic amoebae of man. Philadelphia. Gudger, E. W. 1916. On Leidy’s Ouramoeba and its occurrence at Greensboro, N. C. Jour. Elisha Mitchell Scientific Soc., Vol. 32, pp. 24-32. Hassell, A. 1912. Bibliography of parasitic amoebae. (Over 1000 titles). Trans. 15th Intern. Cong. Hygiene and Demography. Washington, 1913. Jennings, H. S. 1916. Genetics, Vol. 1, pp. 407-543. Jones, I. H. 1918. Equilibrium and Vertigo, 444 pp. 129 figs. Philadelphia. Klemensievicz, R. 1898. Neue Untersuchungen Über den Bau und die ThÄtigkeit des Eierzellen. Mitth. d. Vereins d. Ärzte in Steiermark. 35 Jahr., pp. 45-60. Lynch, V. 1919. The function of the nucleus of the living cell. Amer. Jour. Physiol., Vol. 48, pp. 258-283. Nuttall, G. F. 1901. Blood immunity and blood relationship. London. Pfeffer, W. 1906. Physiology of plants. Trans. by A. J. Ewart, Oxford. Schaeffer, A. A. 1917. Notes on the specific and other characters of Amoeba proteus (Leidy), A. discoides spec. nov., and A. dubia spec. nov. Arch. f. Protistenk. Vol. 37, pp. 204-228. 8 figs. Schaeffer, A. A. 1919. Investigations on the specific characters of Marine Amebas at Tortugas. Year Book No. 18, Carnegie Inst. of Wash., pp. 204-205. Todd, C. 1914. Recognition of the individual by hemolytic methods. Jour. Genetics, Vol. 3, pp. 123-130. Velten, B. 1876. Aktiv oder passiv? Oester. Bot. Zeitschr. Velten, B. 1876. Die physikalische Beschaffenheit des pflanzlichen Protoplasmas. S. B. d. Wiener Akad., Bd. 73. Walton, L. B. 1918. Organic evolution and the significance of some new evidence bearing on the problem. Amer. Nat., Vol. 52, pp. 521-547. Willows, R. S., and Hatscheck, E. 1916. Surface tension and surface energy. 2d ed. Philadelphia. FOOTNOTES: Now, given a unit mass of endoplasm moving at a given instant with a 1 velocity of 1/880 cm. per second against viscosity of ? = .1 dynes per sq. how far will the unit mass travel before coming to rest? Force = Mass × Acceleration, and Acceleration = Velocity/Time. ? = Viscosity = F = MA = MV/T. Now if M = 1, ? = F = A = V/T. T = V/? = 1/880/.1 = 1/88. The space travelled over in uniformly accelerated motion equals S = 1/2 AT² = 1/2 × 1/10 × (1/88)² = 1/154880 = .00000645 cm. If, therefore, the force moving the central stream of endoplasm should suddenly be discontinued, the resistance offered by the viscosity of the enveloping endoplasm would allow it to move only .0000645 mm. before coming to rest. But the ameba as a whole moves more slowly than the central stream of endoplasm, the average rate of movement being about 1/300 mm. per second. The effect of the streaming endoplasm on the forward movement of the whole ameba would therefore be correspondingly decreased. Now if the ameba was perfectly homogeneous and perfectly symmetrical, and free from external stimulation, and moved in a perfectly homogeneous liquid on a perfectly plane surface, the excessively small amount of mechanical inertia would then be sufficient, theoretically, to cause the ameba to move in a straight instead of an irregular path. But these conditions are never realized. The ameba is unsymmetrical in form, heterogeneous in composition and always unsymmetrically stimulated; hence it is impossible that the excessively small amount of mechanical inertia can be considered a factor in determining the direction of the ameba’s path. |
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