43- 



NATURE 



L 



August 30, 1883 



tions of the brain were removed and the whole of its remaining 

 mass were left intact ; this latter culd nevertheless in no case 

 ever take the place of the excided p its. Were, again, only one 

 sphere of sight or one s) here of hearing removed, the animal 

 became blind or deaf on the opposite side, and th : s one-sided 

 blindness or deafness likewise Contii ued throughout the whole 

 of the rest cf the animal's life. Even should only small 

 parts of one sphere of sight or one sphere of hearing 

 be removed, restoration of the functions of these parts never 

 followed. Were, for example, the outer half on the left 

 side of the sphere of sight taken away, the median half of 

 the right retina would then continue blind so long as the animal 

 survived tin's operation. Were the inner half of the sphere of 

 sight taken away, the lateral half of the opposite retina would 

 be rendered blind throughout the rfst of the animal's life. Were 

 the hinder part of the sphere of hearing destroyed, the animal 

 would for the rest of its life continue deaf to deep tone=. Were 

 the anterior half of the sphere of hearing taken away, the ani- 

 mal would be rendered for ever insensible of high tones by the 

 corresponding ear. Even though ever so small pi rtions of the 

 sections in question of the ci rebral cortex were removed, the 

 corresponding part of the retina would be rendered blind, and 

 the animal become deaf to the tones appropriate to the part 

 where the excision was made. It is true that in lime the animal 

 leams to make up for the defects caused by the operations and 

 with the remaining unaffected parts of the retina (supposing the 

 operation has reference to the sight) will contrive to see s i well, 

 and act in genera] in such a way as to superficial observa'ion to 

 convey the impression of an animal endowed with normal powers 

 of sight. On close examination, however, of the particular parts 

 of the retina it will in every case be found that the parts corre- 

 sponding with the excided pari in the central cortex is blind. 

 Functional restoration of an excided part of the cerebral cortex 

 never therefore occurs, however small be the part excided. 

 Otherwise, notwithstanding, it would seem to be the case wiih 

 another function of the sphere of sight which is concerned not 

 with the first visual perceptions but with visual representations 

 or conscious images consequent on perceptions. Has an animal, 

 for example, taken from it the central sphere of sight, it then 

 loses all conscious iu ages ; the mere seeing of objects with the 

 intact peripheral parts of the retina is still possible for it, but 

 not the recognition of them. After some time, however, the 

 animal will regain the power of forming conscious images, and 

 will then recognise the objects it sees. Here, then, we have the 

 restoration of a lost function on the part of the cerebrum. 

 In this rase, however, the functional restoration is, according to 

 Prof. Munk, only an apparent one. The actual state of the case 

 is as follows : — Conscious images are formed in this way. Visual 

 perceptions becoming an object of attention produce visual repre- 

 sentations which give rise in one place of the central organ to a 

 change which, exi. ting as latent conscious image, is aroused by 

 an equivalent or similar visual representation, which in its turn is 

 begotten of perception and attention. These con-cious images 

 have their seat in the central part of the sphere of sight corre- 

 sponding with the central part of the retina, the place of 

 clearest vision. If this central part of the sphere of sight be 

 removed, the animal loses its conscious images, it is soul-blind. 

 According to Prof. "Munk's conception, however, the seat of 

 conscious images lies in the centre of the sphere of sight only for 

 this reason, that usually the visual perceptions coming from the 

 central piart of the retina, and therefore the most distinct, alone 

 become the subject of attention, and are transformed into visual 

 representations. The images of perception, on the other hand, 

 reaching from the peripheral part of the retina to the peripheral 

 part of the sphere of sight, being less distinct, do not become the 

 subject of attention, and are therefore not transformed into visual 

 representations. If, however, with the central part of the sphere 

 of sight conscious images are taken away — if the animal is soul- 

 blind — attention can now fasten only on the images which are 

 seen by the periphery of the retina, the central part being quite 

 vacant in consequence of the operation. In this case, then, 

 visual perceptions in the peripheral parts of the sphere of sight 

 are by attention transformed into representations, w hence now 

 conscious images are drawn. If you render an animal soul- 

 blind on one side, it will never of itself draw conscious images 

 from that side, it will see only with the central parts of the sound 

 eye. If now, however, you blindfold the animal on its visual 

 side, and so compel it to look with the peripheral parts of the 

 side operated on, the soul-blindness on this side will vanish. 

 Restoration is consequently a word totally inapplicable here. 

 On the contrary, all that we here find is that cerebral parts are 



utilised as a re, ository of conscious images, which by the n irmal 

 animal are not turnetl to account simply bei&u e it has other 

 parts with more distinct powers of percepti ui to au-wer its 

 purpi se. The circumstance that former observers have always 

 been impressed with the idea of restoration of sensuous acti- 

 vity is to be explained by the fact that the sphere of sight 

 and the sphere of hearing lie only to a small extent on 

 the surface which is more exposed to injury, and therefore, in 

 the ca>e of a simple excision from the cerebrum, they are 

 always only partially affected. — l'rof. Zuntz related briefly that 

 last year he had inoculated guinea-pigs with bacillse of septi- 

 cemic rabbits and mice, and that they had all escaped harm. 

 When, however, he repealed these experiments this year, the 

 inoculated guinea-pigs all fell sick, but not from se( ticrcmia, but 

 from peritonitis. When, again, rabbits and mice were inocu- 

 lated with bacilla; of guinea-pigs who had died of peritonitis, they 

 I red lepticamia and vice vend. Under the microscope both 

 kinds of baciUse were seen to behave quite alike. 



Vienna 



Academy of Sciences, June 14 — F. Steindachner and L. 

 Doederlein, contributions to knowledge ef Japanese fishes 

 (second paper). — E. Ilann, on the climate of Bosnia and 

 Herzegovina. — C. Etti, on the history of the tannic aci i of 

 oak bark. — M. Neumayr, on the morphology of the valve of 

 bivalves. — L. Teisseyrn, contribution to a knowledge of the 

 Cephalopoda fauna of the Jura in the Kisan Government 

 (Russia). — Zd. 11. Skraup and G. Vortmann, on the derivatives 

 of dipyridine. 



June zi. — II. Hammer), a study on the copper voltameter. — 

 R. Benedikt and M. von Schmidt, notes on halogen derivative . 

 — K. Hazura, on nitro-sulphoresoreinic acid. — H. Bittner, on 

 Micropsis veronensis, a new Echinus of the Upper Italian Ei cene. 

 — Contributions to a knowledge of Tertiary Brachiura fauna. — A. 

 Lieben and S. Zeisel, on the constitution of butyrochloral. — K. 

 Natterer, on dichlorocrotonaldehyde. —J. Kachler and h. V. 

 Spitzer, on the action of the isomeric camphor bromides 1 n 

 nitric acid. — Zd. H. Skraup, a sealed paper on the constitution 

 of quinine. — S. Exner, on the defective excitability of the retina by 

 light of abnormal incidence. — J. Woldrich, on the diluvial fauna 

 of Zuzlawitz in Bohemia. 



CONTENTS Page 



The British Association 409 



Professor Haeckel on Ceylon. By George J. 



Romanes, F.R.S 410 



Our Book Shelf:— 



Klein's " Elements of Histology " 412 



Letters to the Editor : — 



"Elevali n and Subsidence" again. — Rev. O. Fisher; 



Charles Ricketts 412 



" Decentralisation in Science." — R. Meldola . . . 413 



The Earthquake in Isclua. — Cosmopolitan . . . 413 



I ime and Bo: es. — Cosmopolitan 414 



Cop) er and Cholera. — Walter R. Browne . . . 414 



Sulphur in Bitumen.-- Hugh Robert Mill . . . . 414 



Thunder- tonus and Aurora'. — A. Ramsay . . . 414 

 The Meteor of August 19. — A. Trevor Crispin ; 



W. M. Pooley 414 



Stachys palustris as Food. — A. Wentz'l .... 414 

 Oysters, Oyster Fishing, and Oyster Culture at the 



Fisheries Exhib.tion 411; 



United States Coast and Geodetic Survey . . . . 416 



Promise and Performance in Chinese Science , . 417 

 On the Properties of Water and Ice. By J. Y. 



Buchanan 417 



The Stability of Merchant Steamships. By Sir 

 Edward J. Reed, M.P., F.R.S., &c. (With Dia- 

 grams 419 



International Polar Researches. By Dr. Karl 



Pettersen 423 



Notes 424 



Our Astronomical Column : — 



The Division of Biela's Comet 426 



Variable Stars 426 



The Great Comet of 18S2 426 



Geographical Notes 426 



Indian Meteorology, II 428 



Scientific Serials 450 



Societies and Academies 431 



