516 HENRY LAURENS AND HENRY D. HOOKER, JR. 



(17) Kniep and Minder: Zeitschr. f. Bot., 1909, i, 619. 



(18) Blaauw: Rec. d. Trav. bot. Neerl., 1909, v, 207. 



(19) Mast: Light and the behavior of organisms, 1911. 



(20) Laurens: Bull. Mus. Comp. Zool., 1911, liii, 253. 



(21) Day: Bull. Mus. Comp. Zool., 1911, liii, 305. 



(22) Gross: Journ. Exper. Zool., 1913, xiv, 467. 



(23) Yerkes and Watson: Behavior Monographs, 1911, i, 1. 



(24) Yerkes and Eisenberg: Journ. Animal Behav., 1915, v, 27. 



(25) Watson: Dept. Marine Biol., Carnegie Inst., 1915, vii, .87. 



(26) Lashlev: Journ. Animal Behav., 1916, vi, 1. 



(27) Mast: Journ. Exper. Zool., 1917, xxii, 471. 



(28) Coblentz: Bull. Bur. Standards, 1908, iv, 391. 



(29) Coblentz: Bull. Bur. Standards, 1911, i.x, 7. 



(30) Schmidt: Ann. d. Physik., 1909, xxix, 971. 



(31) Pfund: Phys. Rev., 1909, xxviii, 324. 



(32) Pfund: Phys. Rev., 1912, xxxiv, 228. 



(33) Pfund: Phys. Rev., 1912, xxxiv, 370. 



(34) Pfund: Phys. Rev., 1916, vii, 289. 



(35) KuNz AND Stebbins: Phys. Rev., 1916, vii, 62. 



