VARIATION IN EPIDERMAL COLOR IN NAJADES. 285 



5. Hey, W. C. "Fresh Water Mussels in the Ouse and Foss." Journ. 

 Conch. Vol. 3, No. 9, 1882. 



6. Huber, L. von. "Zur Naturgeschichted. Unionen." Jahrbuch des 

 Naturhistorischen Landes Museum V. Karnthen. Heft. 10, p. 155-57 1870. 



7. Israel, W. von. "Die Najadeen des Weidgebietes." Beilage z. Nach- 

 richsblatt d. Deutschen Malakozoologischen Gesellschaft. No. 4, 1910, p. 4. 



8. Jennings, O. E. "A Botanical Survey of Presque Isle, Erie Co., Pa." 

 Annals Carnegie Museum, Vol. 5, 1909. 



9. Marshall, W. B. "Beaks of Unionidae Inhabiting the Vicinity of 

 Albany N. Y." Bull. N. Y. State Museum Nat. History, Vol. 2, No. 9. 



10. Ortmann, A. E. "The Alleghenian Divide and its Influence upon 

 the Fresh Water Fauna." Proc. Amer. Philos. Society, Vol. LII. no. 210. p. 

 275 301, 309, 312, 351, 353- 



11. Ibid. "Notes upon the Family and Genera of Najades." Annals 

 Carnegie Museum VIII, 191 2. 



12. Ibid. "The Najades or Fresh Water Mussels of the Upper Tennessee 

 Drainage with Notes on Synonomy and Distribution." Proc. Amer. Philos. 

 Soc. Vol. 57, 1918. 



13. Ibid. "Monograph of Najades of Pennsylvania." Mem. Car. Musem 

 IV, 1911., VIII, 1919. 



14. Ridgeway, Robt. "The Color Standards and Color Nomenclature." 

 .Published by Mrs. J. Evelyn Ridgeway, 3447 Oakwood Terrace, N. W. 



Washington, D. C. 1914. 53 PI. 11 15 named colors. 



15. Sell, H. von. " Biologische Beobachtungen an Najadeen." Kopen- 

 hagen. Archiv. f. Hydrobiologie und Planktonkunde, 1907-08. p. 129-188. 



16. Simpson, C.T. "On the Mississippi Valley Unionidae Found in the 

 St. Lawrence and Atlantic Drainage Areas." Amer. Nat. Vol. 30, p. 379, 

 1896. 



17. Ibid. "A Descriptive Catalogue of the Najades." Published by 

 B. Walker, Detroit. 



18. Walker, B. "The Unione Fauna of the Great Lakes." Nautilus, 

 Vol. 27. 



