5« 



NA TURE 



[March i i, iqcq 



known. By assuming laws of resistance, the details of 

 portions of trajectories are sketched by the traces which 

 the direction of the axis of the shot and the direction of 

 motion would leave on the celestial sphere.' Mr. Mallock 

 has also studied the physical phenomena of a moving pro- 

 jectile from tile same point of view in a paper on ranges 

 and behaviour of rifled projectiles in air (Proc. Roy. Soc, 

 June 6, 1907), and the two interpretations of the pheno- 

 mena agree in their common portion. Mr. Mallock 's 

 object, however, is to obtain an expression for the drift 

 of the projectile, which he does by assuming that the axis 

 follows the tangent to the trajectory. The present paper 

 is concerned with the details of the motion, the deviations 

 of the axis from the tangent, and with the method by 

 which the axis approximately follows, on the average, the 

 tangent to the trajectory. It is found that in the details 

 lies the explanation of the horizontal and vertical " drifts." 

 — The cross-breeding of two races of the moth Acidalia 

 virqularia : Louis B. Prout and A. Bacot. The authors 

 undertook extensive systematic breeding experiments with 

 the geometrid moth Acidalia iiirgularia (Hiibner) with the 

 view of ascertaining whether there were any " Mendelian " 

 behaviour discoverable in the cross-pairing of two well- 

 marked local races, the dark London form and a white 

 form from the south of France (Hyferes). Between the 

 years igo6 and 1908, ten generations were bred and 

 analysed, the number of specimens being between 5000 

 and 6000. In each generation the two pure strains were 

 maintained, and cross-pairings obtained between them, and 

 many of the hybrids were also carried on to the succeeding 

 generations, although some failed at one point or another. 

 The results were entirely negative so far as .Mendelian 

 segregation is concerned. Hybrids of the first generation 

 presented a facies intermediate between those of the parent 

 stocks, and seldom varying materially. Their offspring, 

 and the .succeeding generations, showed usually a greater 

 variability and a tendency — though indefinite and un- 

 systematic — to revert to, or towards, the original pure 

 forms, but the intermediate or hybrid forms were scarcely 

 ever "bred out," and intergrades from one extreme to 

 the other were so gentle that attempts to sort out hybrid 

 broods into " darks " and " lights " gave only the merest 

 approximations. A few selected pairings, e.g. of light X 

 light ex hybrid, resulted in the recovery of nearly pure 

 strains, so far as it was possible to test them, but nothing 

 peculiar to any special theory of heredity was deducible 

 from them. The authors consider that the behaviour of 

 this hybridisation is confirmatory of that of certain races 

 of Lasiocampa querctts, on which Mr. Bacot had earlier 

 experimented (Entomologist's Record, vol. xiii.), namely, 

 that the bringing together of geographically separated 

 races may be expected to result in the production of blends, 

 and that It will therefore be necessary, In order to obtain 

 segregation of the parental forms in a hybrid race, to 

 pair aberrations inhabiting the same geographical area, 

 where it may be assumed that natural selection has, for 

 some reason, virtually eliminated the intermediates. All 

 the_ recorded instances of this Mendelian segregation with 

 which the authors are acquainted among the Lepldoptera 

 are of this latter class, the forms the pairing of which has 

 produced it being well-defined " aberrations " in the sense 

 In which that word is used by Staudlnger, e.g. Triphaena 

 comes with ab. curtisii, XaiithorhoS ferrugata with ab. 

 wndentaria, .ibraxas grossitlariata with ab. varleyata, 

 talhmorpha dominula with ab. rossica, &c. Some in- 

 cidental observations on the inheritance of some minor 

 characters in the wing-markings, or, in one strain, of 

 nianifest 9 sex-predominance, are noted as probably worthy 

 of further attention, though outside the scope of the present 

 inquiry. 



ATarch 4.— Sir Archibald Gelkie, K.C.B., president, 

 in the chair.— The presence of h,T?m-agglutl'nins, ha-m- 

 "psn.i.ns, and hnemo-lysins in the blood obtained from 

 nif'-ctious and non-infectious diseases in man, second re- 

 port : L. S. Dudgreon. Hacmo-lysins.—\t was found 

 that the blood in fourteen cases of tvphold fever showed 

 ha:mo ysis on nine occasions. Those instances In which 

 hemolysis occurred when the immune seruin was added to 

 normal red cells terminated fatallv. In the remaining 

 cases this action was demonstrated when normal serum 

 NO. 2054, VOL. So] 



was added to the immune red cells. .Vuto-hEemolysIs was 

 proved twice, once during an attack of paroxysmal hjemo- 

 globinuria ; the other case was tertiary syphilis. Iso- 

 haemolysis was found several times when normal serum 

 was added to Immune red cells, less frequently with 

 immune serum added to normal erythrocytes. Haem- 

 agglutinins. — Auto-agglutination was an extremely rare 

 phenomenon. In one instance spontaneous and auto- 

 agglutlnation occurred. In this case auto-hsemolysis was 

 also proved. Further experience has shown that iso- 

 agglutinatlon occurs In normal blood, but not auto- 

 agglutinatlon. Haimolytic agglutinins are present when- 

 ever h;emo-lysins can be demonstrated. The specificity of 

 hfem-agglutinins has been proved, and the absolute 

 specificity of bacterial and haEin-agglutinlns has been 

 completely demonstrated. The agglutination resulting 

 from the Interaction of a serum and certain red cells 

 could be completely prevented by previously saturating this 

 serum with the heated (60° C. for one hour) specific red 

 cells. Saturation of the serum with melanin failed to 

 produce any effect. Phagocytosis. — Haenio-phagocytosls 

 was often well marked. The phenomenon usually resulted 

 from the interaction of immune red cells, normal serum, 

 and normal leucocytes. Haemo-lysins, agglutinins, and 

 opsonins might be present together in a certain sample 

 of serum, or the opsonins and agglutinins together, or 

 opsonins singly. Usually, the agglutinins and opsonins 

 had a distinct relationship. — The influence of glucosldes on 

 the growth of acid-fast bacilli, with a new method of 

 isolating human tubercle bacilli directly from tuberculous 

 material contaminated with other micro-organisms, pre- 

 liminary note : F. W. Twort. This investigation was 

 undertaken to test the action of acid-fast bacilli on the 

 glucosldes and to see how far any fermentation reactions 

 obtained would differ with the various strains of human 

 and bovine tubercle bacilli tested, and also to obtain, if 

 possible, a better medium on which to isolate and grow 

 tubercle bacilli. In all, forty-three glucosldes were tested 

 with acid-fast bacilli, including human and bovine tubercle 

 bacilli, but there was no evidence of fermentation with 

 any of the glucosldes. One glucoslde, ericolin, was found 

 to kill off a large number of species of micro-organisms, 

 especially bacilli of the Colon group and various cocci, 

 but had very little effect on the acid-fast group of bacilli. 

 By means of this glucoside the isolation of tubercle bacilli 

 directly from human sputum contaminated with other 

 organisms becomes quite easy. The glucoside should be 

 made up with distilled water in a 2 per cent, solution ; a 

 lump of sputum Is then placed into a test-tube containing 

 the ericolin and placed at 38° C. for three-quarters of an 

 hour to one hour ; subcultures are then made on to 

 Dorset's egg medium, and pure growths of tubercle bacilli 

 will be obtained in fourteen to twenty-eight days ; the 

 tubes are sometimes contaminated with a few other 

 organisms, chiefly tiny colonies of Streptococci and slow- 

 growing colonies of organisms of the Streptothrix group, 

 but they are so few that they in no way Interfere with 

 the tubercle colonies, which can be easily subcultured. — 

 The effect of heat upon the electrical state of living tissues : 

 Dr. A. D: Waller. Mcthod.^Thc tissue — muscle, nerve, 

 or skin — is led off to the galvanometer by two electrodes, 

 A, B. Warmth Is applied by brief glow of a platinum 

 wire under (not In contact with) .\ or R. Fcstilts are as 

 follows : — 



< ^ Excitation 



The arrows under .A and B Indicate the direction of 

 currents in the tissue In response to local warmth or local 

 excitation at A and at B respectively, ^e.g. If muscle led 

 off at A and B to the galvanometer is heated at B, there 

 is current in the galvanometer from B to A, in the muscle 

 from A to B, as Indicated by the first arrow under B. 

 The local skin-currents both to heat and to excitation are 

 of reverse direction to those of muscle (and of nerve). 



