fattening purposes is where the density of the water is 

 about 1014. This likewise applies to the fattening of 

 Oysters. 



To save the bulk of the spat when free is the great 

 object of Mussel culture ; therefore it is imperative to have 

 the ground of the natural sea bed as free from sand, weeds, 

 and mud as possible, so that the young may have some 

 clean hard substance to which it can attach itself. Ascidians 

 and sponges are very destructive to the young Mussel, as 

 they cover the culch, which would otherwise be favourable 

 for their attachment. 



Mussels have a great many natural enemies, amongst 

 which may be mentioned the Star-fish or Five-finger, the 

 Dog-whelk (Purpura lapillus), the Sea Urchin or Echinus, 

 sea birds, Danish crows, and sometimes rats ; but Star-fish 

 deal the most wholesale destruction. I have known ten 

 acres of a thickly-covered scalp to be almost denuded in a 

 fortnight Last summer I had carted from beds under my 

 control between two and three hundred tons of this fish. 

 The Star-fish will always attack small Mussels in prefer- 

 ence to those of larger growth. It first grasps the Mussel 

 with its five fingers, and when it opens slightly to breathe 

 and feed, it inserts its stomach, or part of it, into the body 

 of the Mussel, when I believe digestion commences, and 

 the Mussel dies and opens its shell, and the Star-fish with- 

 draws its stomach with the meat of the Mussel. This 

 operation I have seen performed in all its stages thousands 

 of times, upon Oysters, Mussels, and Cockles. 



The Dog-whelk bores a hole in the shell of the Mussel, 

 about the size of a small pin-head, and destroys it. 



The Sea Urchin also bores a hole in the shell of the 

 Mussel, but much larger than the Dog-whelk, the hole 

 being about the size of a sixpence. This very rarely 



