go 



Scientific Proceedings (38). 



sulphate, hydrochloride, tribenzoyl-derivative. The free substance 

 and the salts are dextrorotatory. On the basis of this it is assumed 

 that the new substance is a complex of cytosin and of a substance 

 which is not a pentose. This necessitates the modification of that 

 part of the formula of the yeast nucleic acid which gives expres- 

 sion to the form of the union of the pyrimidin bases in the molecule. 



The new assumption is in harmony with all the properties of the 

 nucleic acid ; it also is in harmony with the fact that on distillation 

 of the nucleic acid with hydrochloric acid an amount of furfurol 

 was obtained which corresponded not to 44 per cent, of pentose 

 (as the old formula requires) but to about 25 per cent, which is 

 the required proportion by the modified formula. 



56 (466) 



The reaction of the uterine mucosa towards foreign bodies 

 introduced into the uterine cavity. 



By LEO LOEB. 



\From the Laboratory of Experimental Pathology of the University 



of Pennsylvania. 



I found that the introduction of foreign bodies into the uterine 

 cavity approximately six days after ovulation leads to a rapid 

 transformation of the whole uterine mucosa of the guinea-pig into 

 a maternal placenta. Within 5 or 6 days an extraordinary increase 

 in the size of the uterus takes place ; this is followed by a period 

 in which the pressure upon the newly formed placental tissue 

 enclosed within the uterine muscle wall becomes so great that 

 autolysis sets in and within a few days most of the placental tissue 

 has been transformed into a brownish fluid. 



In these experiments no ovum had previously entered the 

 uterine cavity, the Fallopian tubes having been ligatured very 

 soon after copulation in each case. The introduction of small 

 particles of paraffin, of a very thin glass rod, of the thinnest plati- 

 num wire will serve for this purpose ; since the latter, however, is 

 only in partial contact with the uterine mucosa, it is not as effective 

 as the glass rod or the paraffin. These foreign bodies do not act 

 by separating the constituents of the uterine mucosa, that is, by 



