160 



SCIENCE 



[Jv'. S. Vol. XXXn. No. 813 



quantity of nitrate formed from ammonium 

 sulphate was determined. The following is 

 typical of the nitrification studies of these 

 soils : 



INFLUENCE OF CALCIUM CABBONATE AND MAG- 

 NESIUM CAEBONATE UPON NITRIFICATION IN 

 A MAGNESIAN SOIL 



It will be seen that in amounts exceeding 

 0.25 per cent, the magnesium carbonate added 

 to this soil was positively inhibitive to nitri- 

 fying action; i. e., toxic to the bacteria so im- 

 portant to the nutrition of plants, while the 

 calcium carbonate was favorable up to 2 per 

 cent., the highest quantity tried. That this 

 difference in behavior of the two carbonates is 

 due in part to the character of the soil used 

 is evidenced by the fact that in a similar test 

 using an alluvial soil magnesium carbonate 

 gave greater nitrification than calcium car- 

 bonate.' 



From these results it seems that fairly pure 

 calcium carbonate should be obtained for lim- 

 ing soils already containing quantities of mag- 

 nesium equal to or exceeding the calcium 

 there found; in other words, the lime-mag- 

 nesian ratio apparently exerts an effect upon 

 nitrifying bacteria analogous to its eilect 

 upon some of the higher plants. 



Karl F. Eellerman 

 T. E. EoBmsoN 



Bureau of Plant Industry, 

 Washington, D. C. 



SOCIETIES AND ACADEMIES 



the state MICEOSCOPICAL SOCIETT of ILLINOIS 



The society held its regular June meeting in the 

 Boston Oyster House, Chicago, on Friday evening, 

 June 10, 1910, at 7:30 p.m., after the usual 

 monthly dinner, President M. D. Ewell in the 

 chair. After reading the minutes of the May 

 meeting, Mr. D. C. Potter, of Chicago, was elected 



= Cf. W. L. Owen, " The Effect of Carbonates on 

 Nitrification," Georgia Experiment Station Bulle- 

 tin 81, 1908. 



as an active member. The committee reported a 

 minute in regard to the death of Hervey W. 

 Booth, on January 6, which was adopted, and a 

 copy ordered sent to Mrs. Booth. 



W. F. Herzberg reported some notes of experi- 

 ments in the use of erythrosin, as a staining 

 medium; also gave an account of his making a 

 good working micrometer, using a Zentmayer 

 microtome as a dividing engine, and a crystal of 

 carborundum in place of a ruling diamond. 



C. 0. Boring described the dwarf sunflowers 

 growing far above timber line on the summit of 

 Mt. Wood, in southwestern Colorado, so minute as 

 to show fifty or more plants in the space of a 

 silver quarter-dollar. A discussion followed as to 

 the best preservative medium to permit such 

 flowers to be kept for later study and for perma- 

 nent mounting. 



N. S. Amstutz described the present state of 

 the science of photo-telegraphy — in which he was 

 one of the very first successful experimenters — 

 and showed the difficulties in the way, as shown 

 by the microscope. 



W. F. Herzberg exhibited specimens of the new 

 diatom, Arachnodiscus Herzhergi, and Dr. Ewell 

 exhibited a specimen of Bausch and Lomb's late 

 student's microscope. 



The principal speaker of the evening. Dr. Chas. 

 E. M. Fischer, then gave an address on Spiro- 

 chwta pallida, the germ which is the cause of the 

 dreadful disease, syphilis — a protozoon, not a 

 bacterium. He spoke of the long investigations 

 before it was discovered, and proved to have a 

 causal relation; described the difiiculties of find- 

 ing any stain that would make it visible, and how 

 Dr. Ghoreyeb had, less than a year ago, announced 

 a method of staining by a triple use of osmic acid, 

 lead acetate and sodium sulphite, which requires 

 but a short time, and produces results with cer- 

 tainty that allows of an infallible diagnosis of the 

 presence or absence of this most destructive and 

 incurable scourge. It may be mistaken for some 

 resembling forms, such as Spirochceta huccalis or 

 »S'. refringens. The differentia were described, and 

 the stained specimens were then exhibited under 

 the microscope, using a one-twelfth inch oil-im- 

 mersion lens. 



A very hearty vote of thanks was given Dr. 

 Fischer at the close of his address, and the mem- 

 bers and guests spent the remainder of the evening 

 in the study of the various slides exhibited by 

 Dr. Fischer and others. 



Albert McCalla, 



Secretary 



