CONTAGIOUS DISEASES OF DOMESTICATED ANIMALS. 413 



Billroth, Klebs, and others, and I would not have attempted to name 

 them at all had I found them named or sufficiently described by any one 

 else. Since then I have worked considerably with the microscope, and 

 have become somewhat familiar with the classifications adopted by the 

 Europeans, which, it must be regretted, differ widely, and, owing to 

 almost insurmountable difficulties, are yet unsatisfactory. All, how- 

 ever, seem to agree that those Schizomycetes classed by them under the 

 name of " Bacillus " do not form clusters or colonies (Easen, zoogloecv- 

 masses, gliacoccos, or coccoglia), and do not undergo metamorphoses fi'om 

 globular to rod-shaped Schizomycetes, two things decidedly character- 

 istic of the microscopic parasites of the Schizomycetes family as found 

 in swine plague ; consequently the name adopted, Bacilhis, was not well 

 chosen, and is not suitable. Cohn, considered as one of the best au- 

 thorities, discriminates Sphcerobacteriaj Microhacteria, Desmohacteria, 

 and Spirobacteria, and divides the former in Chromogenic^ Zymogenic^ 

 and Pathogenic Sphwrobacteria. According to his classification the Schi- 

 zomycetes of swine plague, in their globular form, would come under 

 the head of Pathogenic ISphcerobacteria, and in their rod- shaped or stick- 

 like form under the head of Microhacteria, under which he arranges 

 only two species, Bacterium termo, and Bacterium lineola, neither of 

 which is identical to the rod-shaped Schizomycetes of swine plague. 

 Bacterium termo is much more lively in its movements than the latter, 

 which, also, invariably disappears as soon as Bacterium termo or putre- 

 faction bacterium makes its appearance in large numbers, and Bacterium 

 lineola is considerably larger. Bacillus anthracis is classed by Cohn 

 among the Besmobacteria, of which he gives it as a characteristic that 

 the same never form any clusters or zooglcea-masses. Spirobacteria (see 

 sub. lY in drawing in my first report) have been found a few times, 

 but I am convinced their occurrence was accidental. 



Billroth makes a different classification, and objects to a separation of 

 the globular from the rod-shaped Schizomycites, as both forms belong 

 to several species, and constitute only different stages of development. 

 According to his classification the Schizomycetes of swine plague would 

 come under the head of CoC'Cobacteria, and might be called Goccobacteria 

 suis. 



Two of my drawings (one sub. VJJ in my first report, and another 

 one in my second) present club-shaped bacteria or Schizomycetes. These, 

 according to Billroth, are Sel^obacteria, and constitute a higher develop- 

 ment of Coccobacterium. The bright and light-refracting granules or 

 globules which constitute the knob, situated in some of the Hdobacteria 

 at one end, and in others further toward the middle {cf. di-awing in my 

 second report), are capable, according to Billroth, of enduring high de- 

 grees of heat and cold, and may even completely dry up without being 

 destroyed, or losing their germinating power. If moistened and swelled 

 again in a sufficiently wet or watery substance, they will produce a great 

 many very fine and pale spores {micrococcos), which are usually envel- 

 oped in a pale viscous substance (glia) ; such a group of spores, colony, 

 or cluster {gliacoccos or coccoglia), remains for some time together, or at 

 rest. These spores, or micrococcos, can multiply by division, and after- 

 wards either remain together as irregular-shaped clusters, or coccoglia- 

 masses, or in form of chains {streptococcos) ; or, if the glia formation is 

 destroyed, multiply further as single micrococcos. In most cases, how- 

 ever, these spores, or micrococcos, which have come forth from the Relo- 

 bacterium, soon stretch or grow lengthwise, and become rod-shaped bodies 

 (bacteria). In fluids these bacteria, after some time of rest, commence 

 to move, work themselves out of the glia or viscous substance, and 



