( 344 ) 



for glass we have expressly investigated the possibility of' therm ical 

 hysteresis on cooling to the lowest temperatures. In connection with 

 what lias been said in Conmi. N°. 95' we fear that for the above 

 treated difference an irregularity in the behaviour of the place of 

 fusion of the glass points to the platinum bar lias played a part, to 

 prevent which further experiments ought to be made with still 

 greater care. If what we now think probable, is verified, observations 

 in which a difference as the one considered just now, manifests itself', 

 should be rejected. 



Besides the formula of the second degree for temperatures below 

 0°, we have also calculated a formula of (he third degree 



l t = L 



( l + («') ^- + ( l/ ) I — I + (c') I — 



v r ' loo ^ * '\ ïooy v 'woo ' 



for the expansion of platinum between — 183° and -|- 80° by the 

 aid of Bknoit's observations from 0° to -|- 80°, in which formula 

 ("')> (&')> ('') re ^ ei ' t0 tne length at the ordinary temperature imme- 

 diately after the cooling. 



The agreement of 



Benoit and 

 isr vb') 31.6 Kamerlingh Onnes 

 1 and ('lay (1905) 



+ }^° (b') 31.41 ' Scheel (1906) 



Platinum 



is pretty satisfactory. Substitution of Scheel's values for those of 

 Benoit would bring about only a slight change in the first group 

 of coefficients. 



Anatomy. — "On the Development of the Corpus callosum in the 

 lithium Brain." By Prof. J. W. Langelaan. (Communicated by 

 Prof. T. Place). 



The points thai al this moment seem of interest in the history 

 of the development of the corpus callosum have been clearly for- 

 mulated by Rktzhs 1 ) in the form of questions. Two of these are: 

 1. Where does the corpus callosum originate? 2. Of what 



l ) Retzius. Das Menschenhirn. Stockholm 1600. p. (i. 



