156 



DR. E. LONNBERG ON THE 



[Feb. 20, 



existence of a second pancreatic duct. By embryological investi- 

 gations it has been proved that the presence of two pancreatic ducts is 

 the primary condition, which thus is retained now and then in Bos; 

 and two sucb ducts always exist in many Ungulata, as, for instance, 

 Equus, Tapirus, and Rhinoceros. The condition in the Euminantia 

 does not seem to be well known (except in domesticated animals) ; 

 it can, however, be concluded per analogiam that they originally had 

 two pancreatic ducts. In such a case it is evident that two forms 

 like Ovis and Ovibos have been able to reduce one and retain the 

 other, so that this resemblance is no distinct proof of close relation- 

 ship, although it may indicate such a feature. 



The main mass of the pancreas (fig. 8, p. 155) of the Musk-ox 

 is situated round the blood-vessels of the liver, but it extends 

 along the paunch towards the spleen, although it does not seem 

 to quite reach that organ. The pancreatic duct has already been 

 spoken of. 



The spleen of the Musk-ox is not elongate as in Ovis and Copra, 

 but its contour is elliptic, equally rounded at both ends (fig. 9). 

 Its length is (in an adult bull) 21 cm. and its breadth 14 cm 



Fig. 9. 



Spleen of the Musk-ox. 



It is, however, much thicker (4 cm. in preserved state) at the side 

 nearest to the oesophagus, and is flattened towards the other sides. 

 Its shape thus agrees very well with that of the spleen of the 

 Cervicornia (Cervus claplms, Capreoh(s) and Gi raffia, and maybe an 

 ancient character. 



The nostrils have already been spoken of in connection with the 

 muzzle. The septum memhranaceum of the posterior nasal cavity 



