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ARKIV FOR ZOOLOGI. BAND 



n:o 6. 



and width at sutura naso-intermaxillaris. This is however 

 variable as may be concluded from the fact that in the skull 

 from Ulm the height of the nasal opening is about 24,5 and 

 the width 20,5 mm, while the corresponding measurements 



Fig. 3 Palatal view of a skull of a Beaver from Ulm. 



of the skull from Regensburg are 21 and 20,5 mm. Matschie's 

 own measurements of »Castor albicus» (1. c, p. 220) prove the 

 same thing. 



In Matschie's »Gastor balticus» the width of the palate 

 between the first molars is V/t> times as great as the molar 

 is broad, while, according to the same author, the palate of 

 the Elbe Beaver at the same place is equal to the breadth 



