RELATION OF FERTILISERS TO SOIL FERTILITY. 31 



The ratio of absorbed lime to absorbed magnesia increased under the 

 influence of Mn, regardless of whether the plant showed a toxic effect or 

 not. According to the Author, the effects of Mn are largely indirect, and 

 are to be explained by its bringing about a modification in the osmotic 

 absorption of lime and magnesia ; and the toxic effects are chiefly brought 

 about through this modification rather than as a direct effect of Mn itself. 

 As not all species of plants are equally sensitive to modifications in the 

 lime-magnesia ratio, likewise the effect of Mn may be very different in 

 Different species of plants. In practice it has been found that the addition 

 of lime to manganiferous soils increases toxic power ; on the other hand, 

 the addition of soluble superphosphate counterbalances, in many cases, the 

 influence of Mn. 



(Hawaii Forester Agr., 8, 176-8.) The Author assumes the toxic action of 

 Mn in Hawaii Mn soils is due to the action of Ca manganite primarily, 

 and to the secondary action of other salts and acids upon the Ca 

 inauganite. 



J. HUDIG. (Landw. Jahrb., 40, 0)13-044.) In the peat settlement of Groningen 

 jand Dreut plant sickness is evident, especially oat sickness. The cause 

 is the organic matter of the soil. Though Mn in the sick soil is as large 

 as in the sound soil, the addition of Mn salts (MnSO 4 , MnO 2 ) had a 

 beneficial effect on the soil, especially in its after-effects. 



JAMES BURMANN. (Bull. Societ. China., 1911 (IV), 9, 957-959. D. amMgua 

 and D. luiea are indigenous to Switzerland, whilst D. purpurea can only 

 be grown in the garden, and does not reproduce itself. This seems to 

 be due to the fact that the two former do not require Mn, w r hilst the 

 third does. Digitalis leaves grown on soil derived from ferruginous grit 

 in Alsace gave 5 OS of ash, containing 9 02 per cent, of Mn. 0-80 per cent, 

 of Fe, whilst the grit itself contained 43 per cent, of Mn and 4-82 per 

 cent, of Fe. The presence of Mn in the ash serves to distinguish 

 D. purpurea from D. anibigua and D. lutca. 



MASONI GIULIO.. (Staz Sper. Agr. Ital., 64, 85-112.) From the researches of 

 the Author it would appear that Fe cannot be displaced by Mn. MnSO 4 

 in the soil is transformed into an insoluble compound (MnCo 3 ). 



(e) Influence of Manganese on " Aspergillus Niger.'* 



G. BERTRAND. (Compt. Rend., 1912, 154, 381-383.) Taking the utmost 

 precautions to avoid the presence of traces of Mn, it is found that the 

 addition of a minute amount of Fe and Zn does not induce sporulation. 

 The addition of a trace of Mn salt, however, brings about profuse formation 

 of couidia, and the mycelium acquires a velvety black appearance. . . . 

 For sporulation the three metals must be present. Ferrous sulphate contains 

 Mn; the purest commercial specimen contains 0-2 to 0-5 milligram of Mn 

 per gram. 



GABRIEL BERTRAND. (Compt. Rend., 1912, 154, 616-618.) By taking elaborate 

 precautions to secure an artificial culture medium free from Mn, the 

 Author has been able to show that very minute doses of Mn (one part in 

 10,000,000,000) have an appreciable effect in increasing the yield of 

 Aspergillus. Mn was separated in special way (described). Vessels of 

 quartz were employed. 



Miscellaneous and unclassified. 



Ashes of sugar-beet. E. O. v. LIPPMAN. (Ber. 21, 3492-3493.) The Author 

 found boric acid, vanadium, manganese, caesium, and copper in minute 

 quantities. 



Presence of Boron, Lithium and Copper in plants. N. PASSERINI. (Staz. Sper. 

 Agr. Ital., 20, 471-476. Ash of tomatoes, chick-peas, Iris germanica. 

 Boron and lithium were nearly always found, copper also in tomatoes, and 

 in chick-peas, in the proportion of 0-082 per cent, of ash, and in Iris 

 germanica as much as 0022 per cent, of the ash. 



Injurious action of Nickel on plants. E. HASELHOFF. .(Landw. Jahresb., 22, 

 862-867.) ... In order to ascertain the effect of Ni on plants, horse- 

 beans and maize were grown in nutritive solutions, to which NiSO 4 was 



j added (from 2-5 to 50 milligrams per litre). The smaller amount (2-5 per 

 thousand) was sufficient to kill the plant. 



