OF THE BRITISH ISLANDS. 81 



ornamental bands of a darker hue that are developed on a 

 ground of rich chestnut-brown ; and lastly the Solonette, or 

 Little Sole (S. luted), No. 140, rarely exceeding a length 

 of four inches, and having small brown or darker spots 

 scattered over a ground tint of uniform stone-grey. 

 In illustration of the large size to which the ordinary 

 Sole, if left undisturbed, will not unfrequently attain, 

 reference may be made to the casts of a pair from the 

 Irish coast now on view in the Buckland Museum, which 

 weighed together no less than twelve pounds. Their 

 length in each instance closely approaching two feet. 



All of the Pleuronectidse are remarkably elegant swim- 

 mers, propelling themselves through the water by graceful 

 undulations of their entire body. The Soles are especially 

 worthy of notice in this respect, and as has been observed 

 of examples acclimatised in aquaria, possess the faculty of 

 converting their body, with its continuous fringe-like dorsal 

 and anal fins, into a complete sucking-disc, wherewith they 

 can adhere at will to the glass sides of the tank in which 

 they are confined. The scales in the majority of the 

 Pleuronectidse are very beautiful as microscopic objects, 

 being of the ctenoid type, deeply serrated and delicately 

 sculptured. In the Turbot {Rhombus maximus), as a 

 remarkable exception, there are no scales at all, but 

 the surface of the body is roughened with bony tubercles, 

 giving some ground for the anticipation that this form 

 may possibly have been evolved from an ancestral line 

 distinct from that whence the ordinary scale-covered Flat 

 fishes sprang. 



Although the Pleuronectidse are usually regarded as an 

 essentially marine group, one species, the Flounder (Pleu- 

 ronectes flesus\ ascends rivers into brackish and even 

 fresh water. Examples of this fish are on view in one of 



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