Spirillum tenerrimum. Lehm. and Neum. Spirillum I Kutscher (Z. H. xx, 46). Description according to Kutscher Short S-forms, very fine and thin, as a rule with three or four turns. Flagella have not been stained. Gelatin plates present characteristic colonies with a compact center; then a finely granular, thinner zone, which carries a row of anastomosing rays at the edge. In the gelatin stab the growth resembles that of mouse septicemia, and also a gradual liquefaction occurs from above. Upon agar plates the colonies are like dewdrops. Slight cloudiness of nutrient media without pellicle formation. Similar to this is the organism Kowalski has called Spirillum hachaiza.1 It is a fine spirillum, sometimes seen in the intestine of cholera cases, but also in human dejecta in masses (also often by ourselves in the stools of cases of suspected cholera). Regarding it, there is a large amount of literature, but it is not of much value. Kowalski (C. B. XVI, 321). Spirillum serpens. (E. O. Müller.) Zettnow (C. B. x, 689). (Vibrio serpens O. F. Müller, emend. Cohn and Kutscher.) Quite large spirilla, thin, with usually three or four slight, abrupt turns (the length of two turns is 5-6 μ), and with a terminal bunch of flagella containing as many as fourteen. In the gelatin plate culture are formed macroscopically small starlets which resemble somewhat microscopically those of symptomatic anthrax, but the rays at the periphery are arranged more in a radiating manner, and are only slightly matted. The growth gradually settles down, and in the stab sometimes is accompanied by the formation of an air space. Both upon potato and agar it resembles Bact. coli. The nutrient solution is rendered very turbid, sometimes with a delicate pellicle. Vigorous indol reaction. Our picture (56, 1), magnified 1000 times, copied from Zettnow, makes the organism appear very much larger than Cohn's description indicates. Our own descriptions correspond to this. Spirillum tenue. Ehrenberg, emend. Cohn and Kutscher. Thin (0.8), markedly winding threads, usually with two to five turns (4-15), with terminal bunches of very delicate flagella. The 1 Bonhoff makes the very surprising communication that these fine spirilla are degeneration forms (older forms) of a short organism which grows upon gelatin exactly like the Bact. coli, and, in young cultures, presents the picture of the Bact. coli when magnified 1000 times. The rods have two flagella at one end, do not grow on potato, give the nitroso-indol reaction, do not coagulate milk, and form no gas from grape-sugar (Hyg. Rund. VI, 1896, 351). Further communications regarding this interesting organism are expected, but have not yet appeared. gelatin plates show the deep colonies as yellowish, round, finely granular, and sharply outlined; the superficial are similar, but more spreading, thin films. The gelatin stab culture presents a delicate growth in the stab, and yellowish, abundant surface growth, with gradual liquefaction and formation of an air space. No growth upon potato. Nutrient fluid rapidly becomes turbid with a thick pellicle. As Kutscher also remarks, Beijerinck's descriptions of three Fig. 19.-Spir. tenue Ehr., after Migula. forms of Sp. tenue (C. B. L. 1, 1) are not sufficient for identification. Bonhoff found one form deviating somewhat from Kutscher's description; for example, with only two flagella on each side. Spirillum undula. Ehrenberg, emend. Cohn and Kutscher. Relatively large threads; usually to 1, rarely 1 to 3 turns; height and diameter of each turn, 4-5 u. After longer cultivation there are often scarcely any except straight forms. With terminal bunches of flagella, three to fifteen in number. In gelatin plates there occurs only in the depth a slow growth of sharply outlined, finely granular colonies, beneath which the gelatin sinks a little. In the stab culture development takes place in the upper two-thirds of the stab; the growth on the surface of the gelatin is thin, whitish, slightly lobulated, and after ten days sinks slowly into a depression. Grows on potato. Nutrient fluids uniformly cloudy, without pellicle. Recently Zettnow and Kutscher have differentiated from this Spir. undula minus also a Spir. undula majus, which is about one-third larger and grows well on meat-infusion gelatin and agar (C. B. XVIII, 611; XIX, 393). rillum volutans. Ehrenberg, emend. Cohn and Kutscher. only the largest spirillum, but one of the largest varieties of a. The threads are about 2-3 μ thick and spirally wound, the of a turn being 6.6 4, length 13.2; usually there are 24 to 34 In cultures the forms are smaller, similar to the Spir. rubrum. ng to Cohn, they have one large flagellum at each end; accord1. Fischer and Kutscher, a terminal tuft of three to eight long a, which are often plaited together. The colonies in gelatin - at first resemble those of Bact. coli; later the gelatin sinks in, he peripheral parts of the colonies break up. Agar plates are like those of the Bact. coli. In the gelatin stab there is a feeble growth; the surface growth is porcelain white, markedly lobulated, and after ten hours sinks into a depression. Upon potato a dry growth. Nutrient fluid uniformly cloudy, without a pellicle or with a scanty one. Spirillum stomachi. (Salomon.) L. and N. Salomon has described (C. B. XIX, 433,) a very interesting beautiful spirillum, which has not been cultivated, and is never absent from dogs' stomachs. It is also found in cats and rats, and can be readily transferred to mice by feeding. It occurs especially in the glands of the stomach. The cells are flexible, and present long, pointed, spirally bent threads. Flagella are unknown. Motility is assigned to an undulating membrane. A key for their differentiation may be omitted, since only two or three species are known. Spirochete Obermeieri. F. Cohn.1 (Plate 56, VIII and IX.) Literature.-Obermeier (C. f. med. Wiss., 1873, 145); Koch (Mitt. a. d. Ges.-Amte, I, 167); Soudakewitsch (A. P. v, 545); Cohn (Beiträge, 1, Heft III, 196); literature by Afanassiew (C. B. xxv, 415). The personal investigations of these authors are not adapted for use in a text-book. Bacteriologically very little is known. Large, flexible, motile threads, coiled like a corkscrew, with pointed ends, 1 to 26 times as long as the diameter of a blood-cell, usually 20-30 μ. Flagella and spores are not known. 1 Sakharoff discovered, in the blood of geese suffering from an epizootic disease in Caucasus, a motile but not flexible spirochete,— Spirochete anserina Sakharoff (C. B. XI, 203),-through which the disease may be transferred to healthy animals. Details are given regarding it by Gabritschewsky (C. B. XXIII, 365). It was not cultivated. The following may be simply mentioned: Spirochete plicatilis Ehrenberg from marsh-water and the Spirochete of the saliva, which have been often seen but never cultivated. According to F.Cohn (Beiträge, Bd. 1, Heft II, and Heft III, pp. 197, 199), these varieties are not to be distinguished microscopically from the Spiroch. Obermeieri. lis tally found in the blood and spleen of recurrent fever cases, hardly ever during the afebrile periods An expor pered by Naunyn); demonstrated by Karlinski 1. be the cause of a part of the cases of febrile iceros C R12 lt stains readily with the usual anilin dyes. Günther recum mer is that the dried and fixed preparation be preriously freed of part of the albuminous bodies by means of al sectic acid solution. It is not stained by Gram's method. No cultons have so far been successful. According to Pasternatzky, the spirochate may be preserved alive for about ten days if a leech is allowed to fill itself from a case of recurrent fever, and then is kept upon ice. Inoculation experiments have succeeded only upon man and monkeys. The monkeys become sick after about three and a half days, but present only the initial attack of fever and no recurrence. Extirpation of the spleen makes the disease more dangerous for the monkey. APPENDIX I. Actinomycetes. For the limitation of this group and its genera, see page 127. We have conscientiously recorded all that is known to us in the literature regarding forking, branching, etc., in other forms up to this time considered as true bacteria; thus, B. pyocyaneum, B. influenza, B. tetani, B. radicicola, Vibrios,-the cladothrix form of B. murisepticum was immediately retracted by Kitt himself,-and we must naturally acknowledge that these observations make it more difficult to perceive in the branching a distinguishing peculiarity between actinomycetes and fission-fungi. Innumerable similar difficulties are, however, encountered in the definition of higher plant families-some genera are often placed with equal propriety in one or another family. If at a later time, because of further investigations, the significance of branching should be construed in a manner different from that of to-day, it will still remain true in any case that the actinomycetes of to-day, which we have collected in part upon the basis of branching, will form a perfectly natural family, even if their family diagnosis should be essentially remodeled. 1. Corynebacterium. Lehm. and Neum. Cultures having throughout the character of cultures of true bacteria; soft, lying flat and loose upon the nutrient media. Stain well with the ordinary bacterial stains, but are not acid proof. Microscopically: Rods, which frequently present clubbed swellings at the ends, appear more or less distinctly composed of differently staining |