BY R. GREIG SMITH. 117 



gave the following analysis : — 



0-5962 grm. gave 0-5346 grm. BaSOj = 52-62 % Ba. 

 Barium citrate contains ... ... 52*11 % Ba. 



Barium succinate contains ... ... 54-16 % Ba. 



In view of my percentage figures being generally low, it would 

 appear that the salt is a mixture of barium citrate and 

 succinate. 



The solution obtained after distilling the ethereal extract of 

 the calcium sulphate residue was diluted with water wlien a 

 brown insoluble fatty acid separated. This was collected, dried, 

 transferred to a small filter, treated with ether, and the ether 

 evaporated. The residual fatty acid, which was solid at the 

 ordinary temperature, melted at 40-43°, from which it appeared 

 to be lauric acid. 



The mother liquor was boiled with an excess of baryta water, 

 neutralised with sulphuric acid, filtered, and evaporated down 

 to small volume. A salt separated out, and an anal3^sis showed 

 that it contained 51-94 % Ba, from which it appeared to be 

 barium citrate. 



The filtrate from the barium citrate was treated w^ith an 

 excess of sulphuric acid and distilled in a current of steam. 

 No volatile acids passed over. The acid solution was extracted 

 with ether, and the residual acids allowed to crystallise. 

 Colourless prisms imbedded in lauric acid were obtained. The 

 prisms were partly purified by drying them on filter paper at 

 100^; the fatty acid being absorbed by the paper. The crystals 

 were sublimed and a determination of the melting point of 

 the sublimate was made. The sublimate had the same micro- 

 scopical appearance and melting point as sublimed succinic 

 acid. It softened at 175°, and melted completely at 180°. 



From these preliminary results it appears that the acids 

 contained in cultures of the bacteria made in potato extract 

 in the presence of chalk and saccharose consist of acetic, lauric, 

 citric, lactic and succinic, with traces of formic and oxalic. 



Since these acids were found in the potato extract cultures 

 it is probable that in other and more definite media there 



