176 Mr. Swale Vincent. Further Observations upon the 



mode in the case of a random selection from a normal distribution are 

 worked oat. 



5. Analogous results are next obtained for the skew frequency 



curves : 



/ x \™i / x Y ,la 



and V = Vi 7 e -vtan- l a . 



It is shown that in these cases the mean size, variation, modal 

 frequency, and skewness are in general all such that their errors are 

 correlated. Hence any selection of size modifies both the variation 

 and skewness of the distribution. This is of considerable importance 

 for the theory of evolution, as in most cases of zoological frequency 

 the distribution is of the second, or tangent curve, type. Hence 

 random selection of size tends to modify not only variation but skew- 

 ness of distribution. The results are too long to be cited, and their 

 application to special cases involves somewhat lengthy, but not 

 complex arithmetic, which in practical cases we have found much 

 shortened by the use of the " Brunsviga " calculator. 



" Further Observations upon the Comparative Physiology of the 

 Suprarenal Capsules." By Swale Vincent, M.B. (Lond.), 

 British Medical Association Research Scholar.* Communi- 

 cated by E. A. Schafer, F.R.S. Received November 2, — 

 Read November 25, 1897. 



(From the Physiological Laboratory, University College, London.) 



In previous communication st I have given experimental evidence 

 in favour of the view that the paired suprarenal bodies aod the 

 interrenal gland of Elasmobranch fishes correspond respectively to the 

 medulla and cortex of the suprarenal capsules of the higher Verte- 

 brata. I have further stated, as the result of numerous experiments, 

 that the medullary portion of the suprarenal appears to be absent in 

 Teleosts, the suprarenal bodies in this order of fishes consisting 

 solely of cortex. 



Since performing the above series of experiments my attention 

 has been devoted to the general physiological effects of extracts 



* The expenses involved in this research have been defrayed by a grant from 

 the Government Grant Committee of the Royal Society. , 



f 'Physiol. Soc. Proc.,' March 20, 1897; ' Roy. Soc. Proc.,' vol. 61/ p. 64, 1897; 

 ' Arrat. Anz.,' vol. 13, Nos. 1 and 2, L897. 



