478 



STURIONID.E. 



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, having pointed central spines directed 

 backwards, 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 

 ventral on each side ; the flattened plates are marked with 

 radiating 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 striae 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 longest, 

 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 ; and 

 two other representations of the head are given with the next 

 species for comparison. 



