VAUTATION OF CONDITION OF GROUND. 53 



nud, masses of seaweed and beds of so-called '^scruff;" the 

 latter are composed of a few oysters in clumps, great quan- 

 tities of pecten, and polyzoa (Mucronella and Salicoruariada3 

 I have seen in very considerable masses hauled up in the 

 trawl), to such an extent in fact, that the trawl net is some- 

 times unable to bear the weight when being hauled out of 

 the water and breaks away with all it contains. In the 

 late autumn, winter and early spring months, on the other 

 hand, when storms are prevalent, the ground becomes cleared 

 of these obstructions and after trawling for six or eight 

 hours the net may be hauled in with not more than one or 

 two cwt. of debris. 



This frequent alteration of the bottom of the sea, causing 

 as it does variation in the kinds of fish caught and in the 

 invertebrate Fauna, will be of great interest to investigate. 

 It may be added that most of the scruffs lie west of the 

 Eddystone rocks and parallel to the coast line. 



In the following account of the trawling grounds fished 

 by the Plymouth smacks it must be understood, that the 

 localities mentioned for each season of the year are the 

 favourite fishing grounds for that season ; but smacks are so 

 dependent upon the wind and weather that it is not possible 

 for them always to reach or remain on their favourite 

 grounds. 



It may be taken as a general rule that in a strong north 

 wind the smacks fish near in shore ; when the wind is strong 

 from the north-east they choose ground east of the Sound ; 

 when strong from the north-west they take westerly ground. 

 Southerly winds are the most favorable. The trawlers of 

 Plymouth fish, with the rarest exceptions, in at least twenty 

 fathom water ; the average depth fished in is probably 

 between thirty and forty fathoms, while fifty fathoms may 

 be considered as the maximum. 



