11 



These experiments show, tliat the blood from the pancreatic vein 

 at ürst exahs the N. metabolism and then/ lowers it again. Under 

 these circumstances it would not be proper to dwell any longer on 

 these contrary effects, as we are unable to account for them satis- 

 factorily. 



It also appears that the blood favours the permeability of the 

 kidney tubules for sugar. 



This experience throws ligiit on the contrary results in our preceding- 

 series of experiments in which the glucosuria was disproportionate 

 to the sugar content in the blood. It would seem then that the 

 secretuni of the pancreas subserves the function of the kidney as 

 well as the glycogenesis of the liver. Indeed, this has also been 

 admitted by de Meyer and others, however, on a different basis 

 and just the other way about, De Meyer held that the internal 

 secretuni of the pancreas prevented sugar from passing through the 

 kidney. It must be borne in mind, hov;ever, that de Meyer experi- 

 mented with artificial renal cii-culations, which readily lead to para- 

 doxical phenomena. 



Summary. 



1. Secretin decreases the amount of sugar in the blood. 



2. The blood that has passed through the pancreas, is capable 

 of neutralising the action of levorotatory suprarenin on the sugar 

 content in the blood. In this study no effort has been made to detect 

 whether this action is due to a diminished si)litting of the gljTOgen 

 in the liver or [)erliaps to an increase in the formation of glycogen. 

 Presumably the activity of this blood (internal secretuni) is furthered 

 by the injection of secretin. The secretuni is thermostable and is 

 soluble in alcohol. These results are perfectly concordant with 

 De Meijer's experience. 



3. Our experience that the secretum favours the permeability of 

 the kidney for glucose instead of lessening it, clashes with the results 

 of De Meijer's investigations. 



Rotterdam, Dec. 1912. 



Botany. — ''On the nucleolus and kuinjvkinesix in Zj/(/ne)na\ By 

 Prof. C. VAN WissELiNGH. (Commuiiicated by Prof. J. W. Moll). 



(Communicated in the meeting of April 25, 1913). 



Whilst Spirogyra has very often been used for the investigation 

 of the nucleus and nuclear division, Zygnema has so far as I know, 

 up to the present only been studied for this purpose by two inves- 

 tigators. It should be no cause for sui-prise that the latter alga has 



