CHONDROSTOMA NA8US. 195 



commences slightly behind the ventral, half way down the body, and is one- 

 fourth hig-her than the length of its base. The anal fin, which commences 

 far behind the termination of the dorsal, has as long a base as the latter, and 

 its height is equal to its length. The ventral fins do not reach the vent. The 

 pectorals are feebly developed, though their longest ray exceeds those of the 

 ventrals. The caudal fin is evenly-lobed, deeply-forked, and about as long as 

 the head. 



The scales are firmly attached. They vary in form and size in different 

 parts of the body, being sometimes higher than long, sometimes longer 

 than high. The common form of the long scales is sub-hexagonal or sub- 

 ovate, but there are always two remarkable festoons on the fixed border. On 

 the free border there is a fan of six to ten diverging rays. The usual size of 

 the scale in young fish varies from one-fifth to one-fourth the diameter of the 

 eye ; but in old fish it amounts to three-fourths or nine-tenths of the orbital 

 diameter. In fish of medium size the scale is half the diameter of the eye. 

 There are five longitudinal series of scales between the lateral line and ventral 

 fins. The lateral line descends so as to be slightly concave. 



The colour of the back is a metallic blackish-green ; the sides are paler, 

 becoming silvery towards the abdomen. 



The dorsal fin and upper lobe of the caudal are of tlie same colour as 

 the back, but the lower lobe of the caudal is red, like the anal, ventral, 

 and pectoral fins ; in some localities these fins are orange or purple. The iris 

 is brassy, often with a red speck. The skin, but especially in the abdominal 

 region, is covered, like that of many other allied fishes, with points of black 

 pigment. 



Dr. Giinther described from Tiibingen a beautiful coffee-coloured variety, 

 in which the colour was most intense at the tail. The whole fish had a 

 golden lustre, but the scales — which were larger than usual — 'Were boi'dered 

 at the free edge with silver. Similar fishes were previously described by 

 Schsefer from the Moselle as Gh. anratns. 



This species is usually about eighteen inches long, and its weight rarely 

 exceeds three pounds ; but in Central Europe it is brought to market from 

 nine inches to a foot long, weighing one pound and a half. It is not 

 greatly esteemed for food, being one of the most bony fishes known, but 

 reaches the fish markets of France and South Germany in great quantities, 

 where it is bought by the poor at a low price. 



About fifteen tons are taken every year in two or three weeks near 

 Augsburg. 



It spawns in April and May in Germany, Switzerland, the Rhine, and 

 France, when it collects in shoals, and seeks the bottom in gravelly places 



