Scientific Proceedings. 



(135) 7i 



hypertonic sea water, they begin to segment at a temperature of 

 about 1 9 0 C, in from an hour to an hour and ten minutes after 

 they have been removed from the hypertonic sea water. After this 

 they go on segmenting at the rate and usually in the manner char- 

 acteristic of the fertilized egg. The eggs treated with the acetic 

 acid alone, after having formed a membrane, do not begin to seg- 

 ment for about five or six hours (if they segment at all) and they 

 do not develop beyond the four or eight-cell stage, dying as a rule 

 within twenty hours. The treatment with hypertonic sea water, 

 therefore, first accelerates the mechanism of cell division originated 

 by the acid treatment, and second, indirectly through or in addition to 

 this acceleration, increases the vitality or prolongs the life of the egg. 



It is not yet possible to say how the acid brings about its effects. 

 Several years ago the author ventured the suggestion that the proc- 

 ess of membrane formation was due to coagulation. The author's 

 recent experiments, however, contradict such an assertion, inasmuch 

 as the membrane formation never occurs while the eggs are in the 

 acidulated sea water of the above-mentioned concentration, but only 

 after they are taken out and put back into normal sea water. If 

 the process of membrane formation were due to coagulation by acid, 

 it should occur while the eggs are in the acidulated sea water. 



The author considers it possible (but far from proved) that the 

 membrane formation by the spermatozoon and possibly the sub- 

 sequent process of karyokinesis are due to the transitory action of 

 an acid carried by the spermatozoon into the egg or produced 

 transitorily by the spermatozoon in the egg ; and that, in'addition, 

 the spermatozoon carries a second agency or substance into the egg, 

 which supplies some of the conditions produced in the above experi- 

 ments by the brief treatment with hypertonic sea water. 



Twelfth meeting. 1 



Laboratory of Clinical Patlwlogy at the Cornell Medical College. 



May 24, ipoj. Vice President Dunham in the chair. 



34 (80). " Contributions to the study of sulfur. 1. The 

 metabolism in brombenzol poisoning ": W. MACKIM MAR- 

 RIOTT and C. G. L. WOLF. 



Baumann and his pupils investigated the effect of the adminis- 



1 Reprinted from Science, 1 905, xxi, p. 986 ; American Medicine, 1905, ix, p. 

 026 ; Medical News, 1905, lxxxvii, p. 520. 



