MELANOPHORES OF RANA 249 



2. The melanophores of })oth larval and adult frogs lie in pre- 

 formed spaces in the connective tissue and corium, respectively. 

 The melanophores of adult frogs fill the branches of their pre- 

 formed spaces in the fully expanded phase, those of tadpoles 

 do not. 



3. The melanophores of adult frogs have expansion-phase pat- 

 terns which are constant for each cell and which are forced upon 

 the cells by their preformed spaces. 



4. The melanophores of both larval and adult frogs expand 

 and contract within the spaces which enclose them. As the 

 processes of expansion and contraction are performed by means 

 of pseudopodia, these cells are amoeboid. 



LITERATURE CITED 



Ballowitz, E. 1S93 a tjber die Bewegungen tier Pigmeiitzellen. Biol. Cen- 



tralbl., Bd. 13, pp. 625-630. 



1893 b Die Innervation der Chromatophoren. \'erhandl. d. Anat. 



Ges., pp. 71-76. 



1893 c Die Nervenendigungen der Pigmentzellen. Zeitschr. f. wiss. 



Zool., Bd. 56, pp. 673-706. 



1913 tJber chromatische Organe, schwartzrote Doppelzellen und an- 



dere eigenartige Chromatophorenvereinigungen, liber Chromatopho- 



renfragmentation und liber den feinei'en Bau des Protoplasmas der 



Farbstoffzellen. Verhandl. d. Anat. Ges., pp. 108-116. 

 BiEDERMANN, W. 1892 Uber den Farbenwechsel der Frosche. Pflliger's Arch., 



Bd. 51, 455-508. 

 Brucke, E. 1852 Untersuchungcn liber den Farbenwechsel des afrikanischen 



Chamiileons. Denkschr. d. k. Akad. d. wiss. Wien. 

 BuscH, W. 1856 Phanomene aus dem Leben der Pigmentzellen. Arch. f. Anat., 



Physiol, und wiss. Med., pp. 415-424. 

 Degner, D. 1912 Uber den Bau und Funktion der Krusterchroniatophoren. 



Zeitschr. f. wiss. Zool., Bd. 102, pp. 1-78. 

 Ehrmann, S. 1892 Beitrag iur Physiologic der Pigmentzellen nach Versuchen 



am Farbenwechsel der Amphibien. Arch. f. Derm. u. Syphilis, Bd. 



24, pp. 519-540. 

 FiCALBi, E. 1896 Ricerche suUa struttura minuta del'a pelle anfibi. Atti R. 



Acad. Pclor. in Messina, Anno 11. 

 FiscHEL, A. 1896 liber Beeinflussung und Entwicklung des Pigmcntes. Arch. 



f. mikr. Anat., Bd. 47, pp. 719-733. 

 Franz, V. 1908 Die Htruktur der Pigmentzelle. Biol. Centralbl., Bd. 28, pp. 



536-543, 545-548. 



1910 Zur Struktur der Chromatophoren bei Crustaceen. Biol. Cen- 

 tralbl. Bd. .30, pp. 424-430. 



