OYSTER. 



381 



rating what is termed the spawn from the cultch, the 

 former being returned to the beds to preserve the 

 stock for future seasons. After this month it is felony 

 to carry away the cultch ; and it is besides punish- 

 able to take any oyster between whose shells a 

 shilling will rattle when the valves are closed. The 

 reason of heavy penalties being inflicted on the de- 

 struction of the cultch appears to be, that when this 

 is removed, the ouse increases, and muscles and 

 cockles breeding in the beds destroy the oysters by 

 occupying the places where the spawn should be 

 cast. There is also some penalty for not destroying 

 the Asteria (star-fish) found in the neighbourhood of 

 oyster-beds, as they are very destructive to these fish 

 by inserting their rays as the shells lie open, and de- 

 vouring the animals within, a circumstance noticed 

 by the accurate and ancient naturalist Oppian, in the 

 following lines : 



The prickly star creeps on with fell deceit, 

 To force the Oyster from his close retreat. 

 When gaping lids their widen'd void display 

 The watchful star thrusts in a pointed ray, 

 Of all its treasures spoils the rifled case, 

 And empty shells the sandy hillocks grace. 



The principal breeding time of oysters is in April and 

 May, when they cast their spawn, or spats (as it is 

 called by the fishermen), upon rocks, stones, shells, or 

 any other hard substance that happens to be near the 

 place where they lie, to which the spats immediately 

 adhere till they obtain their film or testaceous crust, 

 resembling drops of greenish tallow, and the sub- 

 stances, of whatever nature they may be to which they 

 adhere, are called cultch. From the spawning time till 

 about the end of July, the oysters are said to be sick, 

 but by the end of August they become perfectly re- 

 covered. During these months they are considered 

 out of season, and bad eating. This is known on 

 inspection by the male having a black and the female 

 a milky substance in the gill. Oysters are commonly 

 considered in season after that time till the ensuing 

 year, in the months with an r, beginning with Sep- 

 tember. 



Oysters are not reckoned in high condition for the 

 table till they are about a year and a half old, so that 

 the brood or one spring are not taken for the market, 

 till at least the September twelvemonths afterwards. 

 When younger than these happen to be dredged, 

 they are always again thrown into the sea. The fish- 

 ermen ascertain the age of oysters by the broader dis- 

 tances or interstices among the rounds or rings of the 

 convex shell, which in all bivalves indicate the annual 

 increase. 



Oysters are taken from their native beds by 

 dredges, formed of a net held open by means of an 

 iron scraper, drawn over the beds by a rope attached 

 to a boat. As soon as (hey are thus removed from 

 their beds, they are stored in pits formed for the 

 purpose, furnished with sluices, through which, at the 

 spring tides, the water is suffered to flow. This 

 water, being stagnant, soon becomes green in warm 

 weather, and in a few days afterwards the oysters 

 acquire the same tinge, which renders them of great, 

 value in the market ; but they do not acquire their 

 full quality, and become fit for sale, till the end of six 

 or eight weeks. 



The oysters in the pits are of course always lying 

 loose ; but on their native beds they are in general 

 fixed, from the time they are cast, by their under 

 shell ; and their quality is said to be materially 



affected by their being laid in the pits, with the flat 

 shell downwards, not being, as it is supposed, able, in 

 that position, to retain sufficient water in the shell for 

 the animal's support. 



With regard to the locomotive powers of the 

 oyster, upon which much speculation has been exer- 

 cised, every one at all acquainted with the structure 

 of the animal must have observed that this cannot 

 take place, as is usual with many other bivalves, by 

 means of the foot, for such an appendage is altogether 

 wanting in the oyster. 



The Abbe Dicquemaire, who was a close and 

 accurate observer of the habits and manners of these, 

 as well as other marine animals, assures us that 

 oysters possess the faculty of moving themselves, 

 which is effected by the singular effort of ejecting 

 water with considerable force from their shells, 

 enabling them thus to start to a limited distance 

 backward, or laterally, on one side. He says that 

 any one may amuse himself with the squirting and 

 motions of oysters, by putting them in a plate placed 

 in a horizontal position, which contains as much sea- 

 water as is but just sufficient to cover them. 



The oyster has been considered destitute of motion, 

 and every species of sensation, by most authors ; but 

 the above-mentioned naturalist states that it is com- 

 petent to perform movements, consonant to its 

 habits, either of comfort or defence ; and instead of 

 being destitute of sensation, it is even capable of 

 deriving knowledge, or instinctive reason, from expe- 

 rience. 



When removed from situations constantly covered 

 by the sea, from want of experience they open their 

 shells, lose the nourishment of the water contained 

 in them, and in a few days die. But, when taken 

 from similar situations, and laid down in places from 

 which the sea occasionally retires, they feel the 

 effect of the sun's rays, or of the cold air, or perhaps, 

 apprehending the attack of an enemy, they learn to 

 keep their shells closed till the tide returns. 



Oysters breathe by means of branchiae or gills. 

 They draw the water in at their mouth, which is a 

 small opening in the upper part of the body, drive it 

 down a long canal that constitutes the base of the 

 gills, and so out again, retaining the air for the neces- 

 sary functions of the body. Thus their ejecting the 

 water seems to serve the double purpose of aiding the 

 motion of such as are free, and of supplying the ani- 

 mals with air. These observations are principally 

 derived from the Abbe Dicquemaire, in Philosophical 

 Transactions ; Haak on the Breeding of Colchester 

 Oysters ; and Tuke on the Generation and Ordering of 

 Oysters, in Sprat fs History of the lioyal Society. 



As an article of luxury, oysters were known at a 

 very early period of time. The civilised Athenians 

 held them in great esteem as a dainty food. They 

 were not common at Rome, and consequently brought 

 very high prices ; yet Macrobius assures us that the 

 Roman pontiffs never missed having them every 

 day on their table. Apicius, the third of that 

 name, was excessively fond of oysters, and used to 

 pay for them a most eViormous price. Those of the 

 Lucrhie Lake, and Abydos in the Hellespont, being 

 esteemed by far the best, were sent as delicate 

 presents to men of high rank. The Emperor Trajan, 

 when carrying on war against the Parthians, received 

 from this Apicius several baskets or barrels of them ; 

 and Pliny has not thought it beneath the dignity of 

 an historian to record the names of such persons as 



