LITERATURE CITED. 



BALDWIN, J. MARK. 



1897. Mental development in the child and in the race. Methods and pro- 

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 BERNSTEIN, J. 



1900. Chemotropische Bewegungen eines Quecksilbertropfens. Arch. f. d. 



ges. Physiol., Bd. So, pp. 628-637. 

 BERTHOLD, G. 



1886. Studien iiber Protoplasmamechanik. 332 pp., 7 pi. Leipzig. 

 BLOCHMANN, F. 



1894. Kleine Mitteilungen iiber Protozoen. Biol. Centralb., Bd. 14, pp. 



82-91. 

 BUTSCHLI, O. 



1878. Beitrage zur Kenntniss der Flagellaten und einiger verwandten Organ- 



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 1880. Protozoa, I Abth. Bronn's Klassen und Ordnungen des Thierreichs. 



Leipzig & Heidelberg. 

 1892. Untersuchungen iiber mikroskopische Schaume und das Protoplasma. 



234 pp., 6 pi. Leipzig. 

 CARTER, H. J. 



1863. On Amoeba pfinceps and its reproductive cells, compared with ^V//- 



lium, Pythium, Alucor, and Achlya. Ann. and Mag. of Nat. Hist. (3), 



Vol. 12, pp. 30-52, pi. 3. 



CLAPAREDE^ED., ET LACHMANN. J. 



iS58-'9. Etudes sur les infusoires et les rhizopodes. T. I. 482 pp., 24 pi. 



Geneve. 

 DAVENPORT, C. B. 



1897. Experimental Morphology. Vol. I. 280 pp. New York. 

 ENGELMANN, T. W. 



1882. Bacterium photometricum, ein Beitrag zur vergleichenden Physiologic 

 des Licht- und Farbensinnes. Arch. f. d. ges. Physiol., Bd. 30, pp. 

 95-124. PI. i. 

 1882 a. Ueber Licht- und Farbenperception niederster Organismen. Arch. 



f. d. ges. Physiol., Bd. 29, pp. 387-400. 

 GARREY, W. E. 



1900. The effect of ions upon the aggregation of flagellated infusoria. Amer. 



Journ. Physiol., Vol. 3, pp. 291-315. 

 GROOM, T. T., & LOEB, J. 



1890. Der Heliotropismus der Nauplien von Balanus perforatus und die pe- 

 riodischen Tiefenwanderungen pelagischer Tiere. Biol. Centralb., 

 Bd. 10, pp. 160-177. 

 HARRINGTON, N. R., and LEAMING, E. 



1900. The reaction of Amoeba to light of different colors. Amer. Journ. of 



Physiol., Bd. 3, pp. 9-18. 

 HODGE, C. F., & AIKINS, H. A. 



1895. The daily life of a Protozoan ; a study in comparative psychophysi- 



ology. Amer. Journ. Psychology, Vol. 6, pp. 524-533. 

 HOLMES, S. J. 



1901. Phototaxis in the Amphipoda. Amer. Journ. Physiol., Vol. 5, pp. 



211-234. 



1903. Phototaxis in Volvox. Biol. Bulletin, Vol. 4, pp. 319-326. 

 HOLT, E. B., and LEE, F. S. 



1901. The theory of phototactic response. Amer. Journ. Physiol., Vol. 4, 



pp. 460-481. 

 JENNINGS, H. S. 



1897. Studies on reactions to stimuli in unicellular organisms. I. Reactions 

 to chemical, osmotic, and mechanical stimuli in the ciliate infusoria. 

 Jour, of Physiol., Vol. 21, pp. 258-322. 



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