1014 SUMMARY OF CURRENT RESEARCHES RELATING TO 



cortaiu that the cultivations contain nothing but B. thermophiliis, fresh 

 tubes are inoculated from the last and arc kept at -10^. Tliese tubes 

 remain unaltered. 



The author then isolates his bacillus either by the fractional method 

 or on plates : on the latter it thrives well at a temperature of 60^. 



The microbe is aerobic, and is formed of motionless filaments 

 variable in length and about 1 /x thick. It varies in appearance accord- 

 ing to the temperature at which it is cultivated. At 50' it appears 

 usually as short rods, at one extremity of which is a sinii)le oval highly 

 refractiiiff spore. At 60"^ the filaments are longer and the spores less 

 frequentr At 70° the protoplasm of the filaments assumes a granular 

 look, which in cultivations several days old is almost oily. At 71-72" 

 the bacillus has an almost mouiliform appearance, and spores are alto- 

 gether absent. It cannot be cultivated at a temperature below 42", but 

 between 45" and 70" it thrives very well in a 2 per cent, agar-agar, but 

 the most favourable heat, according to the author, is from G5-70°. 

 Above 70" it grows with considerable difficulty. It is chiefly found in 

 watei-s containing sewage, it occurs also on the soil, but rarely in the 

 air. It has been found in the alimentary canal of men and animals, a 

 fact which seems to show that it is capable of reproduction at from 

 37-40". It is not pathogenic. 



Bacterial Growth at 0° C* — The discovery that certain micro- 

 or<:auisms exist at 0" C. by Dr. Fischer led him to investigate the 

 subiect further, and from the earth and sea-water in the neighbourhood 

 of Kiel harbour fourteen different organisms were found, all growing at 

 0*^ C. Of these, besides the Bacterium phosphorescens and the " endemic " 

 litrht bacillus, three were non-illuminant bacilli, and only one of these 

 fluidified gelatin. Of the remaining nine, one was a fungus of undeter- 

 mined species. Of the eight bacterial forms found in the earth, seven 

 were decidedly rod-like, and four of these caused the gelatin to fluoresce 

 (one with and three without fluidifying). All the foregoing were found 

 to grow at ordinary temperatures also. Their pathogenic properties 

 were not ascertained. 



Cellar Bacteria.t — Piof. A. Hansgirg, as the result of an examina- 

 tion of subterranean bacteria found in cellars, &c., in Prague, arrives at 

 the conclusion that the subterranean forms diff'er little, if at all, from 

 bacteria which develope in the light. He further surmises that the cellar 

 bacteria collected by him have been deposited by chance by drain water, 

 &c., which has percolated through. In consequence, however, of the 

 chauf^ed conditions of the envii-onment, it is advisable to regard certain 

 forms as new species and varieties, of which the following are examples : 



Leptothrix cellaris n. sp. ; Bacillus suhtilis n. var. cellaris ; Leucoiiostoc 



Lagerheimii n. var. stihterraneiim ; Mycoihece cellaris n. gen. et sp. ; Hyalo- 

 coccus cellaris n. s-p. ; Bacterium termo n. \a,i'. sitbterraneum ; Micrococcus 

 suhterraneus n. sp. 



Endosporous Bacteria.^ — Dr. A. Koch describes three new species 

 of endosporous bacteria, and also discusses Bacillus tumescens Zopf, 

 B. alvei Cheshire and Cheyne, and B. Brassicae Pommer. 



* Centralbl. f. Bakteriol. u. Parasitenk., iv. (1888) pp. 89-92. 

 t Oestcrrcich. Bot. Zeitscbr., xxxviii. (1888) pp. 227-30, 263-7. 

 X Bot. Ztg., xlvi. (1888) pp. 277-87, 293-99, 309-18, 325-32, 311-350 (1 pi. aud 

 31 figs.). 



