COMMON STURGEON. 368 



come in their turn to deposit their spawn." The Sturgeon 

 is said to subsist on small fishes ; from the structure of the 

 mouth it probably feeds also on any soft substance that it 

 finds at the bottom. 



The body is elongated ; from the shoulders backward 

 somewhat pentagonal in shape, with five longitudinal rows 

 of flattened plates, with pointed central spines directed back- 

 wards, one row, larger than the others, along the ridge of 

 the back, one row on each side, and another along the edge 

 of the abdomen in a line from the pectoral fin to the ven- 

 tral on each side ; the flattened plates are marked with ra- 

 diating striae. The nose is long and pointed ; the forehead 

 with a longitudinal depression ; the crown of the head ele- 

 vated, the occiput rising into a sharp keel : the mouth placed 

 on the under surface of the head, rather wider than long, 

 with a projecting rim ; no teeth within : about half-way 

 between the mouth and the end of the nose, are four cirri 

 ranged in a line across ; the eyes small ; the operculum 

 hard and strong, covered with strise radiating from a centre ; 

 dorsal fin placed very far back, but little in advance of the 

 line of the anal fin : tail forked ; upper lobe much the long- 

 est, and pointed. The fin-rays in number 



D. 35 : P. 28 : V. 24 : A. 23 : C. 125. 



The colours of the body are various shades of brown ; the 

 plates nearly white, the belly silvery. 



The vignette represents the under surface, of the head. 



