Scientific Proceedings. 



(1*5) 5i 



Cultures of the blood on the thirteenth day (1 c.c. of blood in 

 each of three flasks each containing 50 c.c. of broth and 25 c.c. of 

 ascites fluid) remained permanently sterile. 



Conclusions. — The results of these two experiments permit 

 the conclusion that the virus of measles is present in the blood of 

 patients with typical measles some time at least during the first 

 thirty hours of the eruption ; furthermore, that the virus retains 

 its virulence for at least twenty-four hours when such blood is in- 

 oculated into ascites broth and kept at 37 0 C. This demonstra- 

 tion shows that it is not difficult to obtain the virus of measles un- 

 mixed with other microbes and in such form that it may be studied 

 by various methods. 



20 (66). " The formation of the centrosome in enucleated egg- 

 fragments " : NAOHIDE YATSU. 



To test whether the centrosome is a permanent cell organ or 

 not, Professor E. B. Wilson (1901) made an experiment on the 

 sea urchin egg by treating, with a salt solution, enucleated egg 

 fragments obtained by shaking. He observed that asters contain- 

 ing centriole and capable of division were produced in the enu- 

 cleated fragments. He, therefore, came to the conclusion that at 

 least some of the centrioles in the asters thus formed must have 

 arisen de novo. Some writers criticized his results, saying that the 

 formation of the centrioles in the enucleated fragments observed 

 by him might have been due to the shaking-out of the nuclear 

 fluid into the cytoplasm. Wilson, therefore, suggested that his 

 experiment be carried out by the author in a somewhat different 

 manner — instead of shaking, to cut eggs singly and to treat the 

 nucleated and enucleated pieces separately. The author tried this 

 experiment on the egg of Cerebratulus in the summers of 1903 and 

 1 904. Strict precautions were taken to prevent accidental fertiliza- 

 tion, everything used for the experiment being sterilized. Individual 

 eggs were cut into nucleated fragments (J. c\, fragments containing 

 the first maturation mitotic figure) and also enucleated fragments. 

 The latter were kept for an hour in a solution of calcium chlorid. 

 Then they were transferred to sterilized sea water. Asters were 

 produced in almost all enucleated fragments thus treated. What 

 is more striking, all the asters had centrioles which were identical 

 with those found in the whole eggs subjected to the same treat- 



