132 George A. Sacher 



c. Log lifespan {x) on log brain weight (z). See Equation (3). 



b„ = -325 ± -022 SI, = -02403 



d. Log lifespan (x) on log body weight {y) and log brain weight (z). 

 See Equation (4). 



b^^^ = --225 + -045 



Sl^ = -01730 

 b^^^ = -636 ± -065 



e. Log brain weight (z) on log body weight {y) ; definition of index of 

 cephalization {w). See Equations (5) and (6). 



h^ = -666 ± -025 Sly = -06678 



w = z- -666?/ + 0-888 



f. Log lifespan {x) on index of cephalization (w). See Equation (7). 



b^,^ = -636 ± -143 Sl„ = -08381 



g. Log lifespan (x) on log body weight (y) and index of cephalization 

 (w). See Equation (8). 



K^o = -198 ± -013 



Sl^ = -01730 

 K.., = -636 ± -065 

 h. Relation of log specific metabolic rate (m) to log body weight {y) 

 as given by Brody (1945); regression of log lifespan (x) on index of 

 cephalization (w) and log specific metabolic rate (m). See Equations 

 (9) and (10). 



m = - -2661/ + 1-047 

 h,„„ = -636 6^.„ = --745 



'xw.m 



REFERENCES 



BoNiN, G. VON (1937). J. gen. Psychol, 16, 379. 



BouRLiERE, F. (1946). Annee biol., 22, 249. 



Brody, S. (1945). Bioenergeties and Growth. New York: Reinhold 



Publishing Co. 

 Ciba Found. Symp. Neurological Basis of Behaviour (1958). London: 



Churchill. 

 Comfort, A. (1956). The Biology of Senescence. New York: Rine- 



hart. 

 Comfort, A. (1958). J. Geront, 13, 342. 

 Count, E. W. (1947). Ann. N.Y. Acad. Sci., 46, 993. 

 Dubois, E. (1924). Proc. kon. med. Akad. Wet., 27, 430. 

 Flower, S. (1931). Proc. zool. Soc. Lond., 145. 

 GuMBEL, E. J. (1958). Statistics of Extremes. New York: Columbia 



University Press. 



