657 



substance varying with the size. They ask tiieniselves the question, 

 if tlie h\w found for the Dog may in general also be applied to 

 other species, and give a negative answer to it. '^1 priori, on doit 

 estimer que non, et nous avons soin de dire que notre étude porte 

 sur un cas particulier." (p. 765). In conclusion they say : "II y a 

 done, en passant des petits aux grands chiens, une difference sensible 

 de la composition chimique, et, par suite, l'unilé de poids ne repré- 

 sente pas pour les uns et pour les autres des valeurs physiologiques 

 identiques", fp. 773). 



It is clear, that by Lapicque and by me, independently of each 

 other and unprejudiced, an identical result has been obtained for 

 two very different species of Mammals. If this circumstance increases 

 considerably the importance of this result, then it appears at the 

 same time that neither of us surmised he had found an interindi- 

 vidual exponent of correlation equal for all species. 



Calculating the value of r for the dog found by Lapicque, 

 proportional to the number of obser\ ations used for each comparison, 

 afterwards^) communicated by him, I find it to be := 0.235. When 

 he repeated the investigation applied to Man, which had caused me 

 to find the two above mentioned values of r 0.245 and 0.219, with 

 other evidences, according to the second method, he found for Man 

 0.23 and for Woman 0.224. \ comparison of the averages of 7 

 larger with 7 smaller individuals of an American Squirrel (Sciurus 

 carolinensis), which 14 individuals with a smaller American species 

 (Sciurus carolinensis) (6 individuals) had furnished an exponent of 

 correlation of 0.56, gave an interindividual exponent of 0.20 ^). 

 With two groups of 5 female Moles of Manouvrier I find 0.234 '). 

 The average of these seven observations is 0,228. 



A number of other comparisons, with less good e\idences, however, 

 constantly furnished values that do not differ much from the average 

 found in this way. When I compare the above-mentioned weights 

 of the six largest Bullfrogs of Donaldson (1. c.) with the six next in 

 size of the same species, T find an exponent of correlation of 0,2516. 



1) "Le poids encéphalique en fonction du poids corporel entre individiis d'une 

 même espèce". Bulletin et Mémoires de la Société d'Anthropologie de Paris. Seance 

 du 6 juin 1907. 5™^ Série, Tome 8, fase. 4. Paris 1908, p. 315. 



") Lapicque, "Le poids encéphalique en fonction du poids corporel entre individus 

 d'une même espèce", 1. c p. 327. 



3) There must be errors in Manouvhier's statements (Mémoires Soc. d'Anthrop. 

 Paris 188b, p. 213 and p. 297) concerning two groups, each of 7,cf moles, as the heavy 

 individuals should on an average only possess 1 m g. more brain than the lighter 

 ones: the average likewise points to these errors. Consequently these groups are 

 useless for the calculation of the interindividual r. 



