636 



SCIENCE. 



[N. S. Vol. XXII. No. 568. 



more chromosome than the male {Anasa, 

 Alydus, Protenor) ; in the other type both 

 sexes have the same number of chromosomes, 

 but differ in respect to a particular chromo- 

 some (the ' idiochromosome')? which is smaller 

 in the males than in the females {Lygceus, 

 Euschistus, Ccenus, Podisus). The relations 

 show that these differences must be determined 

 at the time of fertilization, and they arise 

 from the fact that two classes of spermatozoa 

 exist in equal number. In the first type one 

 half of the spermatozoa possess one more chro- 

 mosome than the other half. In the second 

 type half the spermatozoa possess a large idio- 

 chromosome and half a small one. Females 

 are produced in each case upon fertilization 

 by spermatozoa of the first class, males upon 

 fertilization by spermatozoa of the second 

 class.^ 



Experimental Hepatic Cirrhosis in Dogs from 



Repeated Inhalations of Chloroform. C. 



A. Herter and William E. Williams. 



Repeated chloroform inhalations caused, in 

 dogs, an abundant, richly cellular connective 

 tissue growth between and into the hepatic 

 lobules. The bile ducts were proliferated and 

 the liver cells showed much fatty and hyaline 

 degeneration. The percentage of arginin ob- 

 tainable from the proteids of the hepatic tissue 

 was less after the chloroform treatment than 

 that obtainable from the normal tissue. The 

 proportion of fat in the liver cells was also 

 reduced. 



These observations open the question wheth- 

 er the fatty and parenchymatous degenerations 

 of the liver, which in some cases follow nar- 

 cosis by chloroform in the human subject, may 

 not occasionally pass on to interstitial cir- 

 rhosis — a single narcosis in man being suffi- 

 cient to induce the primary damage to the 

 protoplasm of the liver cell. 



Color Sense in Different Races of ManTcind. 



E. S. Wood WORTH. 



The author endeavored to ascertain whether 

 races of mankind which seem to represent the 

 more primitive stages in human development 

 are specially subject to color blindness. The 

 experiments were carried out in association 



* Science, 1905, XXII., p. 500. 



with Mr. Frank G. Bruner, under the Anthro- 

 pological Department of the St. Louis Exposi- 

 tion. Of 252 adult male Filipinos (including 

 Christians and Moros), 14, or 5.6 per cent., 

 were red-green blind. Of 75 males of the 

 ' wild tribes ' of the Philippines (Igorots, Tin- 

 guianes and Bagobos), 2, or 2.7 per cent., 

 were red-green blind. Of 13 male Negritos, 

 none was color blind. A negative conclusion 

 is warranted as to the suggestion that the 

 color sense has developed, within human his- 

 tory, from anything approaching red-green 

 blindness. Various additional results also op- 

 posed the view that the color sense has devel- 

 oped within human history from a more 

 primitive type in which only the red end of 

 the spectrum appeared as colored. 



On the Practical Concentration of Diphtheria 



Antitoxin. E. B. Gibson. 



The author described a new method for the 

 preparation of concentrated diphtheria anti- 

 toxin. The serum is precipitated with an 

 equal volume of saturated ammonium sulfate 

 solution, and the precipitate extracted with 

 a solution of saturated commercial sodium 

 chlorid. The antitoxin globulin dissolves in 

 the latter and the insoluble globulin is sepa- 

 rated by filtration. The antitoxin is sepa- 

 rated from the filtrate by addition of a half- 

 volume of saturated ammonium sulfate solu- 

 tion, or better still, by addition of acetic acid 

 in the usual way. The precipitate separated 

 by filtration is pressed as dry as possible be- 

 tween absorbent paper and dialyzed a few 

 hours in parchment paper. The resultant 

 dialyzed solution is then neutralized and re- 

 dialyzed for several days. A quarter of a 

 per cent, of sodium chlorid and some toluol 

 are added and sterilization effected by double 

 filtration through a Berkfeldt filter. 



The concentrated antitoxin solution thus 

 prepared contains probably from two to three 

 times the proportion of protein present in 

 normal serura. Large quantities of serum can 

 'easily be worked over at comparatively small 

 expense by the method indicated and the 

 product thus prepared is as good or better 

 than ordinary antitoxic serum, in practically 

 all respects. 



