An introduction to practical bacteriology for physicians, chemists, and students / by W. Migula ; translated by M. Campbell and edited by H. J. Campbell.

  • Migula, W. (Walter), 1863-1938.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to practical bacteriology for physicians, chemists, and students / by W. Migula ; translated by M. Campbell and edited by H. J. Campbell. Source: Wellcome Collection.

    39/272 (page 27)
    locomotion. Moreover, it very frequently happens that tliese characfceristics are not all present in one species; many are motionless, and yet form spores, and so on. Continually species are being taken out of the dass Bacterium, to be inclnded in tbe dass Bacillus, and in tbe end the former will probably be quite absorbed in the latter. We soon observe considerable differences in the movements of bacilli. Some shoot like lightniug through the field of vision, whilst others di-ag them- selves slowly forwards, Again, others show oscillatory movements without really moving from one place, whilst yet others swann abont amongst themselves without apparent method, now shooting here, now there, sometimes pausing for a momeut, and then turning round, etc. Many bacilli are quite motion- less, whilst in others these movements may be tem- porarily suspended. Distributed amongst these rod-bacteria, we find the motionless ball-bacteria, or Micrococci, which are already known to us. Specimens of a third family, the Screw or Spiral bacteria, may occasionally be found in the meat infusion, but they more fre- quently occur in an infusion of decomposing plants. They are like little bent rods, which sometimes appear as long threads, twisted into the form of spirals, and sometimes as shorter cells, which present the appear- ance of half the turn of a spiral. The diameter of the