BACTERIOLOGICAL DIAGNOSIS. 737 



movements, it must be remembered that some of the motile bacteria, 

 under certain circumstances, do not exhibit active movements ; the 

 question of motility must therefore not be hastily decided in the 

 negative from a single examination. Spore formation also, in many 

 cases, depends upon special conditions, and great care will often be 

 required in determining this character, which, indeed, is still unde- 

 termined for some of the best-known species. 



We have endeavored in the present volume to include all bacteria 

 which have been described by competent bacteriologists with suffi- 

 cient detail to permit of their recognition when carefully studied by 

 the usual methods. But we have also included a considerable num- 

 ber which are imperfectly described and which could not be identi- 

 fied by the descriptions given. And no doubt a certain number of 

 those which have been described under different names are in fact 

 identical or simply varieties of a single species. The plan adopted of 

 grouping the different bacteria described with reference to their mor- 

 phological and biological characters will bring together those micro- 

 organisms which are similar, and will, we trust, be of assistance to 

 working bacteriologists in determining identity or non-identity. Im- 

 perfect descriptions, if not completed by future researches, may be 

 eliminated hereafter, but we have thought it best to give them a 

 place in this Manual, as most of them are included in systematic 

 works published abroad e. g. , the micrococci found by Koch in his 

 experimental study of traumatic infectious diseases (1878), Bien- 

 stock's faeces bacilli, etc. 



LIST OF BACTERIA DESCRIBED. 

 PART THIRD, SECTION IV. PYOGENIC BACTERIA. 



1. Staphylococcus pyogenes aureus (Rosenbach). 

 Micrococcus of infectious osteomyelitis (Becker). 



2. Staphylococcus pyogenes albus (Rosenbach). 

 Staphylococcus epidermidis albus (Welch). 



o. Staphylococcus pyogenes citreus (Passet). 



4. Micrococcus pyogenes tennis (Rosenbach). 



5. Streptococcus pyogenes (Rosenbach). 

 Micrococcus of erysipelas (Fehleisen). 

 Streptococcus of pus. 

 Streptococcus longus (Von Lingelsheim). 



0. Micrococcus gonorrhceaa. 

 Gonococcus (Neisser). 



PART THIRD, SECTION V. BACTERIA IN CROUPOUS PNEUMONIA. 



7. Bacillus of Friedlander. 



