282 



its extremity to draw the shell after them, as water- 

 snails do. This motion is repeated as long as they 

 please : thus they form a sort of groove in the sand, 

 which sustains the shell on either side, and leaves 

 behind them a sort of irregular tract, three or four 

 yards long. In rivers abounding with muscles one 

 iray see many of them, with a muscle at the end of 

 each. 



That called the arm or a leg in a sea-muscle, which 

 in its natural state is not above two lines long, may 

 reach out of the shell two inches: and the muscle 

 having laid hold o\\ a fixed point, therewith, bends 

 and shortens it and so dra^s itself on. The beard 

 Serves for an anchor to fasten it to some heavy body, 

 that it may not be carried away with the motion of 

 the waves. 



When a pond muscle walks, it thrusfs out its 

 whole belly, inform of the keel of a ship, and creeps 

 on the belly as the serpent does. So true it is, that 

 nature is not confined in her manner of operation, 

 but is every varying, though never confused. 



In Port-Mahon harbour, there are stones from 

 Iralf a hundred to five hundred weight eacn, lying 

 at all depths, full of shells, each containing a single 

 fish of the muscK'-kmd. The holes i- the surface 

 are far narrower tnan the hole in *vhich is the fish, 

 which it seems is capable of enlarging its room as it 

 growft bigger, by abraiding the s zes ol its ceils. And 

 this is .tppireut, from the sandy matter found in 

 the bottom of those cells, whenever the orifice is 

 higher than the bottom ; for then the fish cannot 

 throw it out. 



The Bollani likewise in the Adriatic sea, live in 

 large stotirg. Tneir Shell is rough and obi >ng, not un- 

 like a da.e. Tney are found in several kinds uf por- 

 ous atones, in the pores of these the spawn is de- 

 posited. Fr-.q'iently the aperture, through whic'i it 

 was injected, is nolonger perceivable; but the fish thrives 



