Studies on Chromosomes 39 



observations of Stevens and myself is to demonstrate the existence 

 of a constant and definite correlation between the chromosomes 

 and the sexual characters, which is visibly expressed in the relations 

 of a single pair of chromosomes. These relations unquestionably 

 afford a concrete basis for an interpretation of sex-production 

 that assumes a Mendelian segregation and transmission of the 

 sex-characters and to this extent they accord with the general 

 assumption of Castle. The validity of both this and the alterna- 

 tive interpretation suggested must be tested by further inquiry. 



Zoological Laboratory of Columbia University, 

 December 8, 1905. 



WORKS CITED 



BEARD, JOHN, '02. The Determination of Sex in Animal Development. Fischer, 



Jena. 

 BOVERI, T. H., '04. Protoplasmadifferenzierung als auslosender Faktor fur Kern- 



verschiedenheit. Sitzungsber. der Physikal.-med. Ges. Wiirz- 



burg, 1904. 

 CASTLE, W. E., '96. The Early Embryology of Ciona intestinalis. Bull. Mus. 



Comp. Zool., xxvii. 



'03. The Heredity of Sex. Ibid., xl, 4. 

 CORRENS, C., '02. Scheinbare Ausnahme von der Mendel'schen Spaltungsregel 



fur Bastarde. Ber. d. deutschen Bot. Ges., xx. 

 CUENOT, L., '99. Sur la determination du sexe chez les animaux. Bull. Sci. de 



la France et de la Belgique, xxxii, v, I. 

 '05. Les races pures et leurs combinaisons chez les souris. Arch. Zool. 



Exp. et Gen. (4), iii, Notes et Revue, No. 7. 

 GROSS, J., '04. Die Spermatogenese von Syromastes marginatus. Zool. Jahrb., 



Anat. und Ontog., xx, 3. 

 HENKING, H., '91. Ueber Spermatogenese und deren Beziehung zur Eientwick- 



lung bei Pyrrochoris apterus. Zeitschr. Wiss. Zool., li. 

 LENHOSSEK, M. v., '03. Das Problem der geschlechtsbestimmenden Ursachen. 



Fischer, Jena. 

 McCLUNG, C. E., '02. The Accessory Chromosome. Sex-determinant? Biol. 



Bull., iii, I, 2. 

 MONTGOMERY, T. H., '01. A Study of the Germ Cells of Metazoa. Trans. 



Am. Phil. Soc., xx. 



'04. Some Observations and Considerations on the Maturation Phenom- 

 ena of the Germ-cells. Biol. Bull., vi, 3. 



