400 



TIIK FKKSII-WATKU FISIIKS ()!' KUROPE. 



shields. The squamosal shields are broad, extend back a little farther than 

 the parietal, and are shorter than these shields, but longer than the frontal 

 shields, which converge anteriorly, but do not meet, being divided by the 

 ethmoid plate, which has small ossifications round it, and penetrates a little 

 way between the extremities of the parietal scutes. The post-frontal scute 

 extends quite as far back as the frontal, and forms the upper and hinder 

 border of the orbit. The extremity of the snout is covered with small, 

 star-shaped, irregular plates and bony processes, and shows two rows of black- 



Fig. 190. ACIPENSER GULDEN8TADTII, 

 HEAD SEEN FROM AliOVE. 



Fig. 191. ACIPENSER GULDEXSTADTII, 

 HEAD SEEN FROM HELOW. 



coloured pores. The under side of the snout is covered with large pores, which 

 have somewhat the aspect of the meshes of a net, except in the median line. 



There is a short median ridge in front, feebly developed, and extending only 

 as far back as the barbels (Fig. 191). Its farther course is indicated by a 

 furrow. The barbels are much nearer to the extremity of the snout than in 

 A. schypa, and, when laid back, do not reach near to the mouth. The mouth 

 is large, and occupies nearly the entire width of the under side of the head. 

 The small upper lip is not only deeply notched, but completely divided, though 

 the two halves are in contact. The entire middle of the lower jaw is destitute 

 of lip. The eyes are large, nearly round, the left rather smaller than the 



