52 



SCIENCE. 



[Vol. XVIII. No. 442 



afforded an excellent gathering place for flocks of the nitri- 

 fying organism. The "nitric ferment" does not, as the 

 Frauklands had already shown, grow well upon ordinary 

 gelatine plate cultures; and this is probably the cause of the 

 failure of all previous experimenters to isolate the special 

 ferment. 



Before receiving Winogradsky's paper, in the spring of 

 1890, we had been using in our woi'k, at the suggestion of 

 Mr. Allen Hazen, an ammoniacal solution of the following 

 composition: ammonium chloride (resublimed), 1.907 grams; 

 sodium carbonate, 3.7842 grams; sodium phosphate, .3 grams; 

 potassium sulphate, .2 grams. These salts were dissolved 

 in such a quantity of re-distilled water that the solution con- 

 tained 100 parts of nitrogen per 100,000, and two equivalents 

 of alkali. Ten cubic centimetres of this solution were mixed 

 with one litre of re-distilled water, and then inoculated as 

 desired. The flasks used have been made chemically clean 

 by boiling with potassium pei'manganate. and the water 

 used has been twice distilled. The other rigid precautions 

 absolutely necessary in all work of this character have al- 

 ways been taken. The solutions thus prepared have con- 

 tained from .0001 to .0010 parts per 100,000 of albuminoid 

 ammonia. 



Proceeding with this solution by the method of dilution, 

 we at length succeeded in isolating a nitrifying organism. 

 A flask was first inoculated with a few grains of sand from 

 Tank No. 13, at the Lawrence Experiment Station, and when 

 nitrification was at its height in this solution, a small por- 

 tion was transferred from this to a second flask, and so on. 

 After a large number of unsuccessful attempts, two solutions 

 were finally obtained which nitrified well, but gave no 

 growth upon ordinary gelatine plate cultures, although the 

 plates were allowed to stand for seven days. Microscopic 

 examination of these solutions showed them to be inhabited 

 by a particular form of bacillus, and apparently by that 

 alone. These bacilli are short, of a slightly oval shape, and 

 vary from 1.1 jj to 1.7 /x in length; they are about .8 yu to 

 .9 J.I broad. They are grouped very characteristically in ir- 

 regular clumps, and are held together by a jelly-like mate- 

 rial. Each aggregation is indeed a typical zooglcea. The 

 aggregations of bacteria were found chiefly on the bottom of 

 the flasks, as was also the case with the organism described 

 by Winogradsky. These masses of zooglcea, obtained as a 

 pure culture from a nitrifying solution, resemble significantly 

 the zoOgloea discharged in considerable quantities from the 

 filter tanks at Lawrence. The bacilli stain with some diffi- 

 culty with the usual aniline dyes. .We have not observed 

 independent movement. Owing to the lack of the usual 

 means of diagnosis, it is difficult to determine in a short time 

 whether this species is the same as the one described by the 

 Franklands and by Winogradsky. On one important point 

 there appears to be a difference between our results and those 

 reached by the above-mentioned investigators. The organ- 

 ism discovered by them oxidizes ammonia to nitrite, but car- 

 ries it no further. Our own flasks give complete oxidation 

 to nitrate. Whether this be due to a difference of condi- 

 tions, a difference in the virility of the organisms, or a spe- 

 cific difference in the bacteria, we are not at present prepared 

 to say. The short time at our disposal has made it impossi- 

 ble to settle this and many other questions to our own satis- 

 faction. We are not even prepared to say that there may 

 not have been a mixture of two or more species in our flasks, 

 all agreeing closely in morphological characters, and in giv- 

 ing no growth on gelatine, but differing in important physi- 

 ological respects. Further investigation is necessary to settle 



this and other important points regarding the relations of 

 this organism to the process of nitrification. 



Whether or not we accept the views of Winogradsky, it 

 is certainly worthy of remark, as he observes, that an organ- 

 ism should exist, which, without chlorophyll and in the ap- 

 parent absence of organic nitrogen and of organic carbon, 

 should be able to multiply and thrive upon wholly inorganic 

 compounds. It may be well doubted, we think, whether 

 this is really the case. It seems more reasonable to suppose 

 that exceedingly minute quantities of organic nitrogen and 

 carbon are actually present, and escape detection by our 

 present methods of chemical analysis, although in reality 

 sufficient to nourish generations of bacteria. 



Our own experience, as well as that of previous investiga- 

 tors, seems to be a warning against a too confiding use of 

 the gelatine plate culture in bacteriological work, since in 

 this instance such confidence has left us for a long time in 

 ignorani'e of a common and widespread as well as highly 

 important organism. 



THE PARASITE OF QUARTAN AGUE. 



In the Zeitschrift fur Hygiene (x. 137) appears the first of a 

 series of papers by CaminT Golgi, demonstrating by means of 

 photography the development of the parasite found in malarious 

 fevers. This paper, of which an abstract appears in the British 

 Medical Journal, deals with the amceba malariie febris quartanuf^ 

 the form found in the quartan type. In 1880 Laveran stated that 

 these parasites are present in every case of malaria, and in no 

 other condition, and that they are probably the cause of the dis- 

 ease. His observations have been confirmed by pathologists in all 

 parts of the worW, and at the present time the weight of proof 

 seems to be in favor of his contention. In his paper Golgi claims 

 to have been the first to demonstrate that the different forms de- 

 scribed as occurring in the blood are simply modifications of one 

 form, and, further, that these metamorphoses follow each other 

 according to a fixed law. This development takes place within, 

 and leads to the destruction of the red blood corpuscles. 



At first the amceba-like parasite is small and non-pigmented; it 

 increases in size at the expense of the substance of the blood cor- 

 puscles, becomes pigmented, and, after passing through a series 

 of metamorphoses, finally ends in a process of segmentation. 

 This process of segmentation takes place at the same'time as, or a 

 short time before, the onset of the febrile paroxysm, and has for 

 its object the formation of a new generation of the parasites. The 

 pigment granules stored up in the body of the parasite take no 

 part in this process of segmentation, and hence, on its completion, 

 escape into the blood plasma, where they are seized upon by the 

 white blood corpuscles and cells of the liver, spleen, etc. 



The new brood of parasites at once pass into fresh red blood 

 corpuscles, and so commences anew the cycle of metamorphoses 

 leading up to the nest paroxysm of fever. The period of time 

 which elapses between the entrance of the parasites into the red 

 blood corpuscles and their segmentation is exactly three days, and 

 hence arises the periodicity of the quartan type of malarial fever. 

 During the first and second days the parasite passes through the 

 various phases of its development within the blood corpuscles, on 

 the third day segmentation takes place, the new brood is set free, 

 and fever results; in other words, the period of apyrexia corre- 

 sponds with the endoglobular growth of the parasite. 



Golgi states that a knowledge of these developmental stages is 

 of immense practical importance for the purpose of diagnosis, by- 

 which an almost mathematical degree of accuracy can be arrived 

 at, and that it is no exaggeration to say that by the simple mi- 

 croscopic examination of a few preparations of blood the physician 

 is in a position to tell when the last attack of fever occurred, to 

 foretell the time of the next attack, and further, to recog-nize what 

 type of malarial fever he is dealing with. The simple quartan 

 fever is explained by Golgi as resulting from the development in 

 the blood of one set of the parasites, which ripen every three 

 days, while the double and triple quartan fevers are caused by the 



