226 



HARD WICKE'S SCIENCE- G OS SIP. 



and provided with a flagellum at each end. Spore- 

 forming rods three or four times as long as broad, 

 isolated or united in threads. Spores for the most 

 part somewhat thicker than the rods. 



In various infusions and substances ; most prob- 

 ably also in the rennet-stomach of living animals. 



According to Cohn, it produces the butj-ric fermentation and 

 is also the efficient cause in the ripening of cheese. 



An extraordinary and peculiar power of resistance is possessed 

 by the spores of B. snbtilis and other species. They are 

 not killed off" by boiling, but are thereby excited to speedier 

 germination, which of course brings into consideration the 

 duration of the boiling. A quarter of an hour's boiling does 

 them absolutely no harm, while after an hour most of them, 

 and after two hours all of them are killed. Heating them 

 above 80° C. kills them sooner. They are not affected by 

 poisons and weak acids. 



33. B. trcmuhts, Koch. 



Very similar to the preceding, but more slender 

 and usually also shorter, always with a flagellum at 

 each end. Spores conspicuously thicker than the 

 cells, often lateral. 



On the surface of decaying plant infusions, forming 

 a thick gelatinous membrane, 



34. B. A>?iyIobacit-r, Van Tieghem. 

 Morphologically like B. subtilis, but distinguished 



by the fact, that at certain times it contains starch in 

 its cells, which can be easily recognised by the blue 

 colour produced on the addition of iodine. 



In the cells of laticiferous plants, in decaying plant 

 infusions, etc. 



According to Van Tieghem's first communications, this 

 species is the cause of cellulose-fermentation. Afterwards 

 ,B. Amylobacter (and not B. subtilis) was indicated by him 

 and Prazmowski, (Bot. Zeitung, 1S79, No. 26) as the ferment of 

 butyric fermentation ( Vibrion butyriqiie of Pasteur). According 

 to Prazmowski B. Amylobacter is especially and essentially dis- 

 tinguished from B. subtilis by the mode of germination of the 

 spores. The germinating thread in the former species is pro- 

 truded not at the equator, but at one of the poles of the sphere. 

 But it appears to me inadvisable to found a new species on this 

 distinction, as Prazmowski desires.* 



35. B. Ulna, Cohn. 



Threads broader than in B. subtilis, slightly flexile, 

 with a dense fine-grained plasma. Single cells as 

 much as 10 ft long, 2 /x broad. Spores oblong- 

 cylindrical. 



In various infusions, e.g., of white of egg. 



* As little is known about i?. Amylobacter in England, I 

 append a passage of Van Tieghem concerning it, translated 

 from the Bulletin of the Socicte Botanique de France, 1S80, 

 p. 284. "Ordinarily, as we know, when B. A7i!ylobacter a.Uacks 

 starch-contsining parenchyma, it first dissociates the cells by 

 dissolving their intermediate lamellae ; then it causes the mem- 

 branes of the cells thus separated to swell up, and dissolves them 

 by degrees, without attacking the granules of starch which they 

 enclo.se (as in potato, bean, etc.). In Ailoxa Moschntellina it 

 is quite different. The .Amylobacter still begins, it is true, by 

 destroying the intermediate lamellae, and separating the cells, 

 the punctations of which " (he is speaking of the sub-epidermal 

 layer of the rhizome, macerating in water) " are then open to 

 the outside. Penetrating into the cavity by one of these punc- 

 tations, it proceeds to develop itself there among the starch 

 granules. At the same time it attacks these granules, and 

 causes them by degrees to disappear, without exercising any 

 action upon the cellulose membrane. When it has completely 

 dissolved and absorbed the grains of starch within the cell, the 

 Amylobacter iaxm.?, a brilliant .spore in each of its articulations, 

 and disappears. With its membrane unaltered, and the mass of 

 spores which fills it, the cell then fulfils the part of a sporan- 

 gmm." According to Van Tieghem, it is the action of this 

 saprophyte which causes plant-tissues, immersed in water, to 

 decay. — Tr. 



Appears to be scarcely different from B. subtilis. Interme- 

 diate forms between the two have been observed. 



36. B. Anthracis, Cohn. 



Exactly like B. subtilis, but motionless * and with- 

 out flagella ; cells 4 ^ or more long, very slender, for 

 the most part united into long, often bent, threads. 

 Spores not at all or little thicker than the threads. 



In the blood of animals which have died of splenic 

 fever ; the cause of splenic fever in cattle, sheep, etc., 

 and of " pustula maligna" in man. 



B. Anthracis and the pathological phenomena engendered 

 thereby are the most accurately known of all the diseases in- 

 duced by Schizomycetes. The Bacilli are found without excep- 

 tion in the blood of animals which have died of splenic fever, 

 and it is sought to infer that they are the cause of the disease. 

 So long as only the vegetative threads were known, it was 

 difficult to prove this ; for these are capable^ of living only 

 a relatively short time, and blood which contains them alone 

 soon loses its power of infection. The remarkable thing about 

 splenic fever, however, is that it often breaks out in a neighbour- 

 hood quite suddenly, then disappears for a long time, to appear 

 again just as unexpectedly without any transference from with- 

 out having taken place. From these facts it must be concluded 

 that the contagium can preserve its infectiveness for a consider- 

 able time. The discovery of the spores of />. Anthracis, which 

 nevertheless are formed only in the blood of dead animals, or 

 when the blood of animals affected with splenic fever is slowly 

 dried, explains this long-lasting power. For, moreover, the 

 spores of B. Anthracis possess great capabilities of resistance 

 to external influences, especially to dryness, so that they are 

 capable of further development even after years. These spores 

 are buried in the ground with the bodies of diseased animals 

 which have died, and when there various means of dispersion 

 are open to them. If then they get in any way into the bodies 

 or the blood of cattle, etc., they germinate, the rods which pro- 

 ceed from them multiply in abundance and soon commence 

 their destructive work. 



B. — Pigment-forming Species. 



37. B. ruber, Frank and Cohn. 



Rods 6-8 jx long, scarcely i ju thick, actively 

 motile, isolated or united from 2 to 4 together. 

 Dividing rods sometimes shorter, only 3-4 fx long. 

 Secreting a brick-red pigment, which is different 

 from that of M. prodigiosus. 



On boiled rice. 



38. B. crythrosporiis, Cohn. 



Motile, short, slender rods, partly forming longer 

 threads, in which numerous, oval-oblong, bright 

 shining, dirty red-coloured spores arise. 



On a solution of extract of meat, putrefying infu- 

 sions of white of egg, and putrefying macerations 

 of meat. 



This species forms partly little floating scales, partly continu- 

 ous membranes ; tlie threads finally dissolve to a jelly, 

 thereby freeing the spores, which then sink to the bottom, 

 united in little gelatinous heaps. The species is easily recog- 

 nisable by the dirty red||colour of the spores.J 



W. B. Grove, B.A. 

 (To be continued.') 



Erratum.— In part of last month's issue, the 

 description of fig. 140 is incorrect. It should read 

 "/', an older spherical family; c, part of /'X300." 

 Also, to fig. 137, for " Solles" read " Tolles." 



* This is now known to move at one stage of its existence, 

 and also to form a Zooglcea ; Q. J. M. S., xviii., i63.--Tr. 



