EFFECT ON ECHINODERMS. S9 



occasionally crushed, would, for the most part, survive after their 

 presence on deck\' The sea-pen (Pennatula), unless seriously 

 crushed, readily survives — whether captured by trawl or hook, 

 and would have no difficulty in again taking up its position on 

 the bottom. 'More decided injury is inflicted in many cases 

 on the members of the star-flsh group, which form no incon- 

 siderable part of the food of the cod, haddock, and flat-fishes. 

 Their brittle nature can ill withstand the rude trials of the 

 trawl, and still less the trampling on the deck of the trawler, 

 when the fishes are packed. All suffer more or less, the 

 majority seriously ; the forms most liable being brittle-stars, 

 sea-urchins, and heart-urchins I' Such was the view expressed 

 in the Trawling Report, and, though less pronounced than 

 some more recent opinions, it appears to state the case not 

 unfavourably for the opponents of the trawl. Thus, the sear- 

 cucumbers, or Holothurians, often brought up from the bottom 

 amidst stones and sea-weeds, are, for the most part, uninjured ; 

 and, since they can voluntarily eject their entire alimentary 

 system, and, as the patient and persevering Sir J. G. Daly ell 

 showed, reproduce it without serious inconvenience in about 

 three months, they are not likely to suffer from the hands of 

 the trawler. The cod is a more exacting marauder of the 

 bottom in regard to the smaller Holothurians, since they are 

 chiefly found in its stomach, and not in the trawl. The ' dreg ' 

 of the Zetlandic fisherman, as he searches for 'yoags' (horse- 

 mussels) for bait, is also a more effective engine for the capture 

 of the great ' sea-puddings,' as these Holothurians are called. 

 While the brittle-stars are mutilated, they are by no means in 

 all cases killed. The disk produces new arms where they have 

 been broken off, and even an injured disk is repaired. While 

 many of the sand-stars are entangled in the trawl, the majority 

 escape by being imbedded in the sand, as can easily be shown 

 by using a dredge on the same ground over which many a 

 trawl has passed. The sea-urchins suffer considerably by the 

 trawl in certain regions, as, for instance, in the outer parts of 

 the estuary of the Tay, and it is doubtful if many of those 



1 Traioling Report, 1884, p. 370. 



2 Ihid., 1884, p. 370. 



