916 



A note by the editor at the conclusion of the above article states that 

 Dr. Kornicke has traced the observation of tubercles on the roots of 

 leguminous plants back to 1587, when Dalechanipsin Hiaioria qeneralis 

 plantar um, described Ornithoj)us perpmUlus under the name of Ornitho- 

 podium tuberosum, giving an illustration of the tubercles. The descrip- 

 tion and illustration of the tubercles are said to leave no doubt as to 

 their identity. 



On the presence of an aerobic ferment in straw, which 

 reduces nitrates, E. Breal [Compt. rend., J 11 (l>;t.L'), pp. 0'^l-'r^4}.— 

 Sclilusnig und Miiiitz have stated that the nitric ferment is present in 

 all arable soils. The author announces the existence of another fer- 

 ment, likewise ain(A)ic, but possessing the proi)ert.v of reducing nitrates. 



This organism is found in straw and is probably present in all vege- 

 table refuse. If straw be carefully tested by means of the dii>henylamine 

 reaction, traces of nitrate will in almost every case be found on the sur- 

 face, but if the straw is allowed to remain a few days in water no 

 nitric acid is tbund. although this reagent jtermits of the detection 

 of 1 gram in 10,(MM),0(K).* If increasing quantities of nitrate be added 

 to the water extrat-t of the straw a ra]>id disai)pearance of the nitric 

 acid is observed. 



This reduction of nitric acid is due to a ferment, for if tlie moist 

 straw be stcrilize«l by heat or by an antiseptic, as for example bichlo- 

 ride of mercury, the nitrates no longer <lisai>])ear. For jjurposes «»f 

 observing the closeness with which the f«Minent adheres to the straw, a 

 small (juantity of the latter was pla< cmI in S(M> c. c. of water contain- 

 ing 0.1 gram of nitrate of potash; next morning no nitrate was i)res- 

 ent. The liquid was then divide<l into two etpuil parts between two 

 difterent vessels, and each received 0.1 gram of nitrate of potash, but 

 in oidy one was the straw soaked. After 24 hours the solution contain- 

 ing the straw c<»ntaini'd no nitric acid: the other had not denitritied 

 after "> days. 



For detecting the prescn<-e of nitric acid in a solution, a drop was 

 transferred to a small glass i>late jueviously moistened with a dilute .solii- 

 lion of liydrochloric acid, and dric<l on a warm plate away from the 

 llamc. Alter cooling, a drop of the reagent was added to the tra«'es of 

 the drop of the soluticm. If nitrate was present a blue coloration was 

 ]U(»dnccd. In the case of sfdid bodies an extract with distilled water 

 was niadt' and the solution tested in the same manner. 



Fxi)eriments by the author showed that this ferment does not reduce 

 the nitrates to ammonia, as is the case in putrescent fennentation, 

 nor to the lower oxid«'s which Deherain and Manpienne have foimd 

 to be formed in vegetable mold by an ai-robic ferment, but that free 

 nitiogeu is the product of the reduction. 



* The sulphate of fliphenylaniinc wn 8 prepared as follows: Boil pure sulphurie aeid 

 to drive out traces of uitric arid wliich it may routaiu. After cooling dissolve in 

 100 jiiams of the acid 1 gram of diplienylauiine which has previously bceu washed 

 aud dried, autl add 25 c. c. of distilled water. 



