May 24, 1907] 



SCIENCE 



813 



properties, depending largely on experi- 

 mental conditions. 



The third component is changed in its 

 hemolytic properties by exposure to washed 

 blood corpuscles. Part, at least, of this 

 change is due to the giving off into the 

 third component of antilytic corpuscle 

 products. No actual absorption of the 

 third serum component by washed corpus- 

 cles has as yet been demonstrated. 



On th& So-called Physical Chemistry of 



Hemolytic Serum: W. H. Manwabing, 



Indiana University. 



Two physico-chemical laws have been 

 proposed for hemolytic serum: (i.) a law 

 governing the interaction of amboceptor 

 and complement. 



When heated hemolytic serum is exposed 

 to washed corpuscles, three phenomena take 

 place: (i.) A hypothetical absorption of 

 amboceptor; (ii.) A change in the third 

 serum component; and (iii.) a giving off 

 into the serum of antilytic corpuscle prod- 

 ucts. No measurement of the amboceptor- 

 power of exposed heated hemolytic serum 

 will, therefore, give any idea whatever of 

 the amount of unabsorbed amboceptor it 

 contains. 



Similarly, the existence of an active third 

 component, which differs in different sera 

 prepared under identical conditions, pre- 

 vents the experimental proof or disproof of 

 the physico-chemical law proposed for the 

 interaction of complement and amboceptor. 



The physical chemistry of hemolytic 

 serum is, therefore, beyond the present 

 power of experimental science. 



On the Chemical Inactivation amd Begen- 

 eration of Complement: Hideyo Nogu- 

 CHi, Rockefeller Institute. 



On the Electric Charge carried hy Toxins, 

 Antitoxins, and Agglutinins: C. W. 

 Field, Research Laboratory, New York 

 Board of Health. 



I. An Improved Technic for Tuierculo- 

 Opsonic Preparations. II. Some Sug- 

 gestions concerning the Terminology of 

 Opsonic Theory and Practise: A. P. 

 Ohlmachee, Detroit. 



Generic Characters in the Coccacece: C.-E. 



A. "WiNSLOw and Anne F. Rogers. 



The difficulties in the classification of 

 bacteria arise partly from the variations in 

 certain characters produced by slight 

 changes in the environment, but chiefly 

 from the fact that characters which appear 

 to be constant for the individual exist in an 

 almost infinite number of minute grada- 

 tions in different races. Extreme differ- 

 ences in any property are completely con- 

 nected by a series of intermediate forms. 

 The best basis for a natural classification is 

 the statistical study of a large series of 

 individuals, which will disclose the points 

 about which the largest number of races 

 are grouped, which are presumably the 

 type centers round which the organisms 

 vary. A study of 500 cultures of cocci 

 isolated from various sources has been made 

 with this end in view. It has shown that 

 the variations which exist group themselves 

 on normal ' curves of frequency.' These 

 show in some cases a single mode, as in the 

 fermentation of dextrose and lactose, all 

 the cultures studied grouping themselves 

 about a single center, and in other cases 

 more, as in gelatin liquefaction, where two 

 centers exist, one for the liquefying and 

 one for the nonliquefying forms. Chromo- 

 genesis shows four centers of variation, the 

 white, yeUow, orange and red forms being 

 quite definitely separated. 



The most significant result of this study 

 is the fact that differences in the various 

 characters are strikingly correlated with 

 each other and with the source from which 

 the organisms were derived. For example, 

 the orange chromogens are parasitic forms 

 which never show the sarcina grouping, are 



