October 12, 1893] 



NATURE 



575 



In the afternoon the section divided into the two departments 

 bf Physiology and Zoology. In the former, the following papers 

 _were read :— (l) On the digestive ferments of a large Protozoon, 

 by Prof. Marcus Hartog and Augustus E. Dixon. The authors 

 experimented with about 2000 large individuals of Peloniyxa 

 palustris, and found that the watery extract hydrolyses starch 

 paste in a neutral solution, and converts the starch rapidly into 

 erythro-dextrin, has no action on thymolised milk in two days, 

 liquefies fibrin rapidly in presence of dilute acids, only attacks 

 fibrin very slowly and partially in neutral solution, and indol 

 and skatol are not formed. (2) On the effect of the stimulation 

 of the vagus on disengagement of gases in the swim- bladder of 

 fishes, by Dr. Christian Bohr (Copenhagen). This showed that 

 the air secreted in the bladder is largely composed of oxygen. 

 The paper was illustrated by tables showing the increase in the 

 proportion of oxygen at stated times during the refilling of the 

 bladder after puncture. (3) On a method of recording the heart 

 sounds, by Prof. W. Einthoven. (4) On nerve stimulation, by 

 Prof. F. Gotch. The author finds that with the induction cur- 

 rent he obtained excitation of the nerve of a frog at a low tem- 

 perature which disappeared at a higher temperature, while with 

 the discharge of a condenser the result was the reverse of that. 

 He also found a similar difference in action in regard to the 

 passage of the impulse down the nerve in the two cases. There- 

 fore he comes to the conclusion that the impulse started in the 

 nerve is somewhat diflferent in the two cases. (5) On faiigue of 

 nerves, by Prof. Schafer. (6) On Calorimetry, by Dr. A.Waller. 

 This applied more particularly to the temperature difference of 

 the body under varying conditions of the surrounding medium. 

 (7) The report of the committee on the physiological action of 

 the inhalation of oxygen in asphyxia. The results are as fol- 

 lows : — (i) In the case of asphyxiated rabbits, oxygen is of no 

 greater service than air ; (2) pure oxygen when inhaled by a 

 healthy man far five minutes produces no effect on the respira- 

 tion or pul-e ; (3) oxygen produces no effect upon a patient 

 suffering from cardiac dyspncea,either on respiration or on pulse ; 



(4) an animal can be kept for a long time in a chamber contain- 

 ing 50 per cent, of carbonic acid without muscular collapse, 

 provided a gentle strea n of air or oxygen be allowed to play 

 upon the nostrils. 



In the Zoological Department the following papers were 

 read: — (i) Report of the committee appointed to explore the 

 region of the Irish Sea lying around the Isle of Man. The 

 committee have conducted eight dredging expeditions, most of 

 them lasting for several days ; about 1,000 species of marine 

 animals have been collected and identified, of these thirty-eight 

 are new records to the British fauna, 224 are new to the district, 

 and seventeen are new to science. Prof. Herdman gave a 

 general account of the expeditions and the results attained, 

 while Mr. A. O. Walker, .Mr. I. C. Thompson, Mr. Stebbing, 

 and Prof. Brady gave more detailed accounts of special groups 

 of Crustacea. (2) Report of the committee on a deep-sea tow- 

 net. (3) On luminous organs in Cephalopoda, by W. E. Hoyle. 

 These minute light-producing organs are scattered over the 

 general integument in certain species. (4) On the origin of 

 organic colour, by F. T. Mott. This was to show that the 

 colours in going from stem to blossom indicate a decrease in the 

 amount ol light absorbed, and the author contends that the 

 amount of reflected light increases as the plant attains maturity. 



(5) On thi." roots of Lemna, and the reversing of the fronds in 

 Lemna ininor, by Miss Nina P". Layard, who showed that in 

 dry seasons, when the fronds dried up, the root-cap would act as 

 a protector for the tender cells of the root. Miss Layard 

 accounted for the observed reversal of the fronds as cases where 

 a growth had covered the upper surface, and the fronds had re- 

 volved in order to expose a better surface to the air. 



The section met on Saturday forenoon, when the following 

 papers, chiefly botanical, were taken : — (i) Report of the com- 

 mittee on the legislative protection of wild birds' eggs. This 

 was read by Dr. Vachell, and supported by Prof. Newton, who 

 urged the necessity of making known to the schoolboy which 

 birds' eggs ought to be protected. (2) On the aetiology and life- 

 history of some vegetal galls and their inhabitants, by C, B. 

 Rothera. The author traced out the life-history of certain 

 typical galls, those of Cynips kollari, Teias termiiialis, and 

 Biorhiza aptcra being specially dealt with. He gave a series of 

 facts positive and negative, which point to the action of the 

 embryo, and not to the deposit of a special virus by the parent 

 Cynips, as the direct and necessary agent in the production of 

 ihe gall. He therefore discards the hypothesis of a specific virus 



NO. 1250, VOL. 48] 



deposited by the parent, and attributes the genesis and metamor - 

 phoses of the gall to the activities of the living embryos com- 

 bined with the normal forces of the plant. (3) Report of the 

 Committee on the Botanical Laboratory at Peradeniya, Ceylon, 

 where a good deal of the apparatus requires to be renewed. (4) 

 On some new features of nuclear division, by Prof. J. B. Farmer. 

 This paper, illustrated by microphotographs, included some new 

 results of researches on the centrogomesand the behaviour of the 

 achromatic spindle. (5) Variations of fecundity in Trifolium 

 pralense and its varieties, and Trifolium medium, by W. 

 Wilson. This paper detailed some observations made as to 

 varieties of clover, contrasting them with hybrids as regards 

 fertility. (6) Lime salts in relation to some physiological pro- 

 cesses in the plant, by Dr. J. Clark. The action of lime sr.lts 

 may modify the effect of low temperatures in seed germination. 

 The author had succeeded in finding a ZfaciY/Kj which is capable 

 of breaking up the calcium oxalate, which is at one time precipi- 

 tated in the plant. (7) On the cortex of Tmesifiteris ianneiisis, 

 by R. J. Harvey Gibson. This gives an account of the histology 

 of the cortex of the stem, with special reference to the origin and 

 nature of the " brown deposit " seen in the cells. 



On Monday a joint meeting with Section C was arranged, 

 when a discussion on " Coral Reefs " was opened by Prof. W. J. 

 SoUas, F.R.S. 



Prof. Sollas said that the problem before the Sections was to 

 explain the presence of large groups of atolls in the deep ocean, 

 every atoll in some of the groups, save for the land piled up by 

 the breakers, rising just up to the level of the sea. The two 

 fundamental difficulties which had to be met were the existence 

 of a submarine bank and the presence of a lagoon, which some- 

 times attained a depth of 60 fathoms or more. Volcanoes had 

 once been supposed to furnish by their cones the bank, and by 

 their craters the lagoons. Possibly some individual atolls might 

 be explained in this way, but not whole groups. Chamisso, 

 postulating a submarine bank, accounted for the lagoon by the 

 fact that corals grow fastest in the wash of the surf. In this way 

 a lagoon 9 or 10 fathoms in depth might be formed, and some 

 of the Florida reefs might be so explained. Dr. Murray accounted 

 for submarine banks by the precipitation of organic sediment on 

 volcanic cones, and for the lagoon by an explanation similar to 

 Chamisso's, which he supplemented by supposing that the cen- 

 tral part of the shoal was i-emoved by solution. There was, 

 however, no evidence that lagoons were deepened by solution, 

 and much opposed to it. Deposition, and not solution, occurred 

 in the lagoon, and so long as an atoll remained stationary the 

 lagoon tended to become filled up. 



Darwin, instead of meeting each difficulty by a separate as- 

 sumption, proposed a theory which, by a single assumption, in 

 itself very probable, accounted for all the facts. One of the 

 gravest objections to Darwin's view had been the apparent ab- 

 sence of coral reefs resembling atolls in ancient systems of 

 rocks. That had been removed by the labours of geologists, 

 who were able to point to atolMike limestones, from 400 to 800 

 fathoms in thicl-ness, in the Tyrol, the Eastern Alps, and else- 

 where. Elevali m had recently affected some existing atolls, as 

 might naturally be expected in an unstable area. That fringing 

 reels, barrier reefs, and atolls should occur together in a single 

 area proved, when the facts were examined in detail, to furnish 

 a striking confirmation of the theory, since these different kinds 

 of reefs were not confusedly intermingled, but arranged along 

 lines which showed a progressive change from elevation at one 

 end to subsidence at the other. The arrangement of atolls in 

 linear series, curving in the Pacific, and straight in the Indian 

 Ocean, was in accordance with the outlines of the surrounding 

 continents, and pointed to deep-seated structure in the earth's 

 crust. Most remarkable in connection with this was the fact 

 that individual atolls were elongated in the same direction as 

 the group of which they formed a part. This was readily ex- 

 plicable on Darwin's theory, but not by the supposition that the 

 elongation was determined by oceanic currents, since these cut 

 the atolls in various direction?, not correlated with that of their 

 longest diameter. Further, the areas in which subsidence had 

 occurred were in many cases just those where geologists had 

 reason for supposing that land had existed in secondary times. 

 Particularly was this true of the Indian Ocean, across which, as 

 Neuuiayer had shown, a great tract of land had probably ex 

 tended in the Jurassic period. 



Dr. Hickson (Section X>) said that he agreed with Prof. Sollas 

 in thinking that the Darwinian hypothesis was both clear and 

 beautiful, but that that was about the only point in which he 



