SOILS FEKTILIZEES. 321 



Experiments on the effects of temperature and moisture on the soil protozoa 

 showed " that some, at least, of the protozoa iu soils lead an active life and are 

 capable of multiplying to quite a considerable extent when the conditions be- 

 come favorable." 



It was found that soil protozoa in solution exercised a very decided limiting 

 effect on the numbers of bacteria. The results on ammonification in solution 

 tests did not, however, justify definite conclusions, although it is thought that 

 the flagellates may have a depressing influence on ammonification. 



Keductiou in bacterial numbers iu the soils inoculated with protozoa was 

 found to be very marked and to lie well outside the limits of exi)erimental er- 

 ror. " The conclusion may safely be drawn, therefore, that the limitiug factor 

 or at least one limiting factor (of Russell and Hutchinson) has been inoculated 

 into the sterilized soils and has produced its effects on the numbers of bac- 

 teria." 



A preliminary communication on three new proteomyxan rhizopods from 

 soil, T. GooDEY (Arch. ProUstenk., 35 (1914), No. 1, pp. 80-102, pis. 4).— The 

 following organisms isolated from soil by means of an agar plate method are 

 described: Lcptonnjxa reticulata n. g. and n. sp., L. flabellata n. g. and n. sp., 

 and GcpJij/ramocba delicatula n. g. and n, sp. 



The methods used are described, and a bibliography of literature bearing on 

 the subject is given. 



Sterilization or disinfection of the soil, Mi6ge {Bui. Soc. Nat. Apr. France, 

 Ut {1914), ^0. 4, pp. 428-432). — This note, reviewing briefly previous experi- 

 ments by others in soil sterilization, gives a condensed account of the author's 

 work carried out at Rennes during 1912 and 1913 with barley and white mus- 

 tard planted in soil treate^l with different strengths of various disinfectants in 

 solutions or in gaseous form. 



While in case of some treatments, as with baryta and creosote, the results 

 were unfavorable, it is claimed that in several others large increases of yield 

 were obtained as the result of the soil treatment, notably by the use of toluene 

 or formaldehyde. 



Suggestions for judging the agricultural value and adaptation of land, 

 W. P. Brooks {Massachusetts Sta. Circ. .J// {1914), PP- 8).— This is a brief 

 sratement regarding the possibility of estimating the productive capacity and 

 adaptation of land by examination on the sjwt. The most important factors to 

 be observed are (1) the depth and color of the surface soil, (2) the level of the 

 water table and the conditions affecting drainage, (3) the soil texture, (4) the 

 general appearance and texture of the subsoil, and (5) the character of natural 

 and spontaneous vegetation. 



The chemical analysis of soils, "W. P. Beooks {Massachusetts Sta. Circ. 45 

 {1914), pp. 4).— This is a revision of Circular 29 (E. S. E., 24, p. 713). 



The crop experiment and soil analysis, O. Lemmermann {Landiv. Vers. 

 Stat., 85 {1914), No. 1-2, pp. 141-154).— The author agrees with Mitscherlich 

 <E. S. R., 31, p. 217) that in fertilizer experiments all the environmental fac- 

 tors, particularly the physical properties of the soils used, exert an influence on 

 the crop yield and must, therefore, be kept constant in order to determine the 

 effect of varying the amounts of a particular nutritive element. In determin- 

 ing the plant food content of soils and the relative solubilities of the nutritive 

 elements he is of the opinion that the best method is to allow the solvent used 

 to filter through the soil sample at a fixed rate of speed. 



Investigations at the Jasper County experiment field, M. F. jNIiller and 

 R. R. HuDELSON {Missouri Sta. Bui. 119 {1914). pp. 30, figs. 7).— This bulletin 

 gives the results of field exi)eriments with a four-year rotation of corn, cow- 



