14:S *rHE PHILOSOPHY 



again make Its appearance. If you do not handle the ani- 

 mal, by applylug fait, you may make it come to the furface 

 as often as you incline ; and fifliermen often make ufe of 

 this ftratagem. This behaviour indicates more fentiment 

 and recolle£lion than one ftiould naturally expeft from a 

 fpout-fifli. 



The fcallop, another well known bivalved fliell-iifh, has 

 the power of progreflive motion upon land, and likewife of 

 fwimming on the furface of the water. When this animal 

 happens to be deferted by the tide, it opens its fhell to the 

 full extent, then (huts it with a fudden jerk, by which it often 

 rifes five or fix inches from the ground. In this manner it 

 tumbles forward till it regains the water. When the fea is 

 calm, troops, or little fleets of fcallops, are often obferved 

 fwimming on the furface. They raife one valve of their fUell 

 above the furface, which becomes a kind of fail, while the 

 other remains under the water, and anfwers the purpofe- of 

 an anchor, by fteadying the animal, and preventing its being 

 overfet. AVhen an enemy approaches, they inftantly fhut 

 their fhells, plunge to the bottom, and the whole fleet difap- 

 pears. By what means they are enabled to regain the fur- 

 face, we are flill ignorant. 



With regard to the locomotive faculty of the oyfter, the 

 following fadls are recorded in the Journal de Phyfmue by 

 the Abbe Di^quemare. Like many other bivalved fhell-fifh, 

 the oyfter has the power of f quirting out water with a con- 

 fiderable force. By thus fuddenly and forcibly ejedling a 

 quantity of water, the animal repulfes fuch enemies as en- 

 deavour to iaflnuate Into its fhell while open. By the fame 

 operation, if not firmly attached to rocks, to flones, or to one 

 another, the oyfler retreats ba,ckwards, or flarts to a fide in 

 a lateral direcSlion. Any perfon may amufe himfelf with the 

 fquirting and motions of oyfl:ers, by putting them in a plate 

 fituated in a horizontal pofition, and which contains as much 



