234 



SCIENCE. 



[Vol. V., No. 11], 



effects of contrast as of sensation. Take a card, 

 white on one side, and half green and half white on 

 the other, with a dot in the centre of each side, to 

 hold the attention. Look steadily at the green-and- 

 white side for a minute, then turn the card, and the 

 half corresponding to the green will have a red tint, 

 and the other half will have a complementary green 

 tint. The consecutive red image has developed, hy 

 induction, the green sensation in a part of the eye 

 which had been impressed only by white. The same 

 results are obtained if the subject be hypnotized. 

 The experiment will fail if the subject is blind to the 

 suggested color. If a subject is blind to a certain 

 color, a peculiar case results. On giving him the 

 hallucination of green, the sensation of red cannot 

 be induced ; but in giving the hallucination of red, 

 which he can see, the induced sensation of green (to 

 which he is blind) is produced. 



The production of consecutive images is a normal 

 phenomenon : so, in all hallucinations which last a cer- 

 tain time, a consecutive image follows. If one causes 

 a patient in a hypnotized state to look at a square of 

 white paper with a point in the centre, suggests that 

 the square is red, and then suddenly presents a sec- 

 ond similar square, the subject will say that the point 

 is surrounded by a colored square, and the color will 

 always be the complementary of the one suggested. 

 This complementary color is the negative image left 

 by the hallucination. It lasts only a short time, then 

 becomes effaced. That similar phenomena are ob- 

 served in the normal condition, may be proved by 

 the following: if, with the eyes shut, we keep the 

 image of a bright color in our mind a long time, then 

 open them suddenly, looking upon a white surface, 

 we will then see for a short time the image we were 

 contemplating, but of a complementary color. 



The following most curious experiment upon the 

 mixture of imaginary colors helps to prove the same 

 thing. Place two squares of differently colored paper 

 at some distance upon a table; then place before the 

 eye a plate of glass inclined in such a manner that 

 the whole of one card can be seen directly, and at the 

 same time a reflected image of the second. One can 

 very readily cause the two papers to superpose, and 

 become mixed. If we show a hypnotized patient the 

 same thing, substituting blank cards, and suggesting 

 colors for each card, they will appear mixed to him 

 in the same manner. The necessary conclusion from 

 this seems to be, that hallucination of a color is a sug- 

 gested sensation, having the same cerebral seat as the 

 real sensation. 



THE OYSTER-FISHERY IN CONNECTI- 

 CUT. 



The fourth annual report of the shell-fish commis- 

 sioners of the state of Connecticut was recently 

 issued, and contains, in concise form, much useful 

 information. In its record of benefits accrued to the 

 state by its system of ownership and moderate taxa- 

 tion of oyster-planting grounds, it offers great en- 

 couragement to those who would institute in each 

 state systematic business methods in connection with 



this one of the most important of all our fishery 

 interests. We have before referred to the system 

 adopted by the commission in mapping and deter- 

 mining permanent bounds for the natural beds and 

 ground available for planting. The survey of the 

 natural beds, which are open to all oystermen under 

 certain restrictions, has been completed. They com- 

 prise 5,805 acres. The total area of planting-grounds, 

 designated for occupancy by the commission since 

 its organization, is 45,046 acres, which have netted 

 to the state $49,560. Adding to this the area pre- 

 viously designated by the seaside towns, and we 

 have over 79,018 acres now under the control of in- 

 dividuals, of which 14,066 acres are under cultiva- 

 tion. 



The total number of tax-paying cultivators in 1884 

 was 385, of whom 16 own each five acres or less, 53 

 between five and twenty acres each, and 332 own 

 twenty acres or more each. The amount of tax lev- 

 ied, averaging ten cents per acre, was about $6,500, 

 of which less than $50 are delinquent. This is tri- 

 fling in comparison with the local taxation of grounds 

 under town jurisdiction. Eleven hundred acres of 

 grounds in the state of Rhode Island pay a tax or 

 rent of a hundred dollars per acre to that state. The 

 Connecticut commission has not valued grounds for 

 taxation in excess of fifty dollars per acre, though 

 lands have been reported sold during the year at from 

 two to six times that amount. It is obvious, there- 

 fore, that the encouragement given by the state to 

 those employed in this business is very great. The 

 business is steadily growing. There are already over 

 three hundred sailing-vessels and forty steamers 

 employed, the latter with an aggregate capacity of 

 36,720 bushels; and several more steamers are being 

 constructed. The first steamer was employed less 

 than ten years ago. 



There has been a very considerable increase in the 

 sale of seed oysters and stock to neighboring states, 

 and also in the exportation to Great Britain. Oys- 

 ters for export are packed in barrels containing 950 

 four-year-olds, or 1,500 three-year-olds, the deep valve 

 down and pressed very solid. One firm, exporting 

 10,000 barrels a year, has never lost a bushel by long 

 passage, bad weather, or other causes. Many are 

 shipped to California also. Accurate statistics are 

 not available, as the oystermen seem to resent in- 

 quiries as an interference with their private business. 

 In the course of time they will probably know their 

 own interests better. 



The chief injury sustained in the business is from 

 star-fishes, which destroy the young oysters. It is esti- 

 mated that over fifty thousand bushels of stars were 

 destroyed last year. They are most destructive in 

 the cooler weather. In July and August they form 

 into great bunches or rolls for spawning, and lie quiet. 

 In some localities there were few or none, in others 

 such multitudes as had not been seen for many years. 

 It has been suggested that the state should pay a 

 small bounty for them; and, as they are worth some- 

 thing as a fertilizer, the sale would partly reimburse 

 the outlay. The receipts of the commission were 

 $13,731.84; the disbursements, $8,350.49. 



