588 TEN YEARS IN SWEDEN. 



Gen. Trygon. 



Body form like the other species,, but the tail is armed on 

 the top with one long-pointed spine, serrated on both edges ; 

 no dorsal fin ; caudal ends in a point like a whip. 



179. T. PASTINACA, L. Spjut Eocka. The Stingy Kay. D. 



Body smooth ; above grey-brown ; below white ; nose 

 short but pointed ; attains a length of 2 ft. to 3 ft., 

 rarely more. 



Has only once been taken on any Scandinavian coast^ 

 and this was an example 15 in. long, from the tip of the nose 

 to 'the spine on the tail, and about 13 in. broad between the 

 points of the pectorals ; the tail spine was 3-- in. long, of 

 which 2i in. was free. This specimen was taken off the 

 southern coast in July, 1849. 



Sect. 2. CYCLOSTOMI. Eound-mouthed Fishes. 

 Gen. Marsipdbrancliiij Bp. 



Gills fixed, purse-shaped, opening outwards by several 

 apertures. 



GROUP 1. Hyperoartiaj Mull. Nostrils lie on the upper 

 part of the head, and lead to a blind bag without a hole 

 through the gums. 



Gen. Petromyzon, Art. 



Body like an eel ; gill openings, seven small holes in a 

 row on each side of the neck, at the back of the eyes ; mouth 

 round, encircled with a fleshy skin, and furnished with teeth . 

 no pectorals or ventral s, and no true anal fin ; two dorsals. 



180. P. MARJNUS, L. Hafs Nejonogon. The Lamprey. D.F. 



Dorsals close together, the hinder one not joined to 

 the tail. Colour, marbled black, and yellow-red; 

 dorsal distinct. The largest taken on these coasts have 

 not been more than 2 ft. long, and about 2 in. high, 

 weighing about 2 Ib. ; but they are taken much larger 

 in southern seas. 



