COREGONUS LAVARETUS. 339 



whole Salmon tribe, to the patience and genius of Dr. Giinther. It is a lake 

 fish, widely distributed in the great lakes of Switzerland, the Tyrol, and 

 Sweden; Ladoga, Onega, and Peipus in Russia; Madua See in Pomerania, 

 and it occurs in Mecklenburg. It frequents the Baltic, and is found in the 

 Haffs on the Prussian coast. It is everywhere valued for food (Fig. 164). 



In Sweden it is known as Sik, or Knubb sik, or Helge sik, which in Russia 

 becomes Sig, a name applied indifferently to many species, for in that country 

 as many as thirty-five varieties have been named. In Northern Germany it is 

 Mardne or Selmdpel, in Bavaria it is Bodenrenke, and in the lakes of Austria 

 Kropjling and Kindling, and in Lake Constance Sandfelcken or Weissfelclien. 



Its size varies with the locality, being only fourteen to fifteen inches long, 

 with a weight of half a pound, in the Austrian lakes, while in Lake Constance 



Fig. 164. COREGONUS LAVARETUS (LINN.TKt'8). 



and the Prussian lakes it reaches a length of two feet or more, and a weight 

 of four to six pounds. 



The greatest height of the body exceeds 'the length of the head, and is twice 

 the thickness. The fish is five times as long as high ; the head is larger than 

 in C. wartmanni. The upper jaw is obtuse, longer than the lower, with the 

 snout obliquely truncated, so that the thick blunt nose projects forward as in 

 Chondrostoma. The mouth is large and the maxillary bone extends below 

 the front part of the fatty eyelid. It may be from one-third to little more 

 than one-fourth the length of the head. The supplementary maxillary bone 

 is semicircular, broad, and short. The eye is nearly one-fifth of the. length of 

 the head, and is separated by its own diameter from the snout. It is more than 

 its own diameter from the other eye. The half-moon-shaped fold in front of 

 the eye is rather large but variable, and the pupil ex tends to wards it, as in other 

 species of the genus. A wide mucus-canal developed behind the eye, becomes 

 narrow in the suborbital region, and is often prolonged forward below the 

 nares in Swiss and other southern specimens. The opercular bones are strong 



