1919'] Proceedings of the Academy of Scie^tce 9 



anteriorly aud in the middle third of the organ become covered with 

 small eggs which never become functional. The anterior third of 

 each ovisac is the functional ovary and its walls are lined with huge 

 eggs each in its follicular sac attached to the wall of the ovary by a 

 long pedicel. 



This paper, which was illustrated by drawings and photographs, 

 will shortly be published by the Carnegie Institution of Washington. 



A Parasitic Blue-Green Alga. W. C. Coker. 



In April of last year we collected in a ditch at the Golf Links near 

 Wilmington, IsT. C, a species of Saprolegnia that I am treating as a 

 form of S. anisospora DeBary. Cultures made in the ditch water 

 with Alga, etc., in which the species was taken showed a remarkable 

 abnormality. A good many of the oogonia were much swollen to 

 as much as twice the average size, while the eggs, which were no 

 greater in number than usual, were in great part disorganized, often 

 only one or two maturing. The disorganized eggs would usually 

 reach the point of forming a thin wall, and would then go to pieces 

 inside. This condition was not thoroughly realized until after the 

 culture had been purified on agar and the abnormality thus arrested. 

 It was then found from slides that the enlarged oogonia contained a 

 parasitic organism with the exact appearance of a blue-green alga, 

 which ran among the eggs. There was not the least resemblance to 

 the ordinary fungal parasites that attack the Saprolegnias, and it is 

 to be regretted that the parasite was lost before it could be more 

 thoroughly studied. 



Investigations of the Nitrotoluenes. James M. Bell. 



The four principal products of nitration of toluene are o-nitroto- 

 luene, p-nitrotoluene, 1-2-4 dinitrotoluene and 1-2-4-0 trinitrotoluene. 

 All of these are of interest in the manufacture of cxj^losives and of 

 dyes. As the analysis of mixtures of these by ordinary chemical 

 methods is impossible, indirect methods of analysis only can give 

 the composition of such mixtures. A method of finding compositions 

 of binary mixtures and of ternary mixtures of the last throe nitro- 



