THE GRAYLING 



England and that the secondary strata to the south-east of it dipped 

 towards the west, causing the waters of the Thames valley to drain 

 westward into the Severn valley. Then, after the Severn valley had been 

 well established, these chalk and eocene beds received a slight tilt towards 

 the east, perhaps in connexion with the earth -movement which caused 

 the subsidence forming the North Sea and promoting the erosion of the 

 Straits of Dover. This eastward tilt sufficed, in Sir Andrew Ramsay's 

 opinion, to create a new watershed and a new river, the Thames, which 

 scooped out its channel through the chalk and overlying eocene beds. 

 This would account for the absence from the Thames and its tributaries 

 of the grayling and the burbot, which the rivers of Yorkshire, Derbyshire 

 and East Anglia derived from their former connexion with the Rhine. 

 Having mentioned that remarkable fish, the burbot (Lota vulgaris) I 

 must crave leave to drag it in to support my view of the original distri- 

 bution of the grayling in Great Britain. It is a solitary species in the only 

 genus of the Gadidce or cod family inhabiting fresh water, and is widely 

 distributed in the rivers of Europe, Asia and North America. Burbot, or 

 eel-pout, are found in Britain only in the eastern-flowing rivers of York- 

 shire and East Anglia, including the Trent and its inland tributaries.* 

 It does not inhabit the Thames, though it has been held to have done so 

 once on the strength of a statement in Leonard Mascall's " Booke of 

 Fishing with Hooke and Line" (1590). The passage has been repeatedly 

 quoted, without a most misleading printer's or reader's error being 

 detected. 



" There is a kind of fish in Holand [that is, the south-eastern divi- 

 sion of Lincolnshire] in the fennes beside Peterborrow, which they 

 call a poult; they be like in making and greatness to a whiting, but 

 of the cullour of a loch [loach]; they come forth of the fennes brookes 

 into the rivers nigh there about, as in Wandsworth river there are many 

 of them.** 

 This has been interpreted, not unnaturally, to mean the Wandle, which 

 runs through Wandsworth into the Thames; but Mascall was treating 

 only of the waters of the Fen district, and what he meant was not *' Wands- 

 worth " but " Wansford," a village on the Nen, about six miles west of 

 Peterborough. 



It is uncertain whether grayling are indigenous in the Itchen and Test. 

 •• There be many of these fishes," wrote Izaak Walton, " in the delicate 



'The recorded capture of a single burbot in the Plym can only be explained as an escape from captivity. 



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