ENTEROCOCCUS 205 



streptococcus saprophytics, which is without haeniolytic action. It should 

 be noted that on blood agar the pneumocoecus forms green colonies and 

 produces little or no haemolysis. Levy finds that a 2 '5 per cent, solu- 

 tion of taurocholate of- sodium in bouillon produces complete bacterio- 

 lysis of the pneumocoecus and the streptococcus mucosus, while it has 

 no effect qn other varieties of streptococcus. He considers the strepto- 

 coccus mucosus to be a variety of pneumocoecus. On the other hand, 

 some strains of streptococcus mucosus have been found to be insoluble 

 in bile-salts ; hence two varieties have been distinguished {vide p. 231). 

 The general statement may be made that most of the streptococci from 

 lesions in the human subject have hsemolytic action, but that occasionally 

 streptococci without this property are found even in severe infections. 



A combination of fermentative and hsemolytic tests has also been used 

 in classification, and this appears advisable. For example, Holman takes 

 the presence or absence of haemolysis as the first basis of classification. 

 The two groups thus obtained are subdivided into four, according to the 

 action on lactose ; these again into eight, according to the action on 

 mannite ; and finally these into sixteen, according to the effect on salicin. 

 Blake employs the same principle but omits mannite, and does not sub- 

 divide the hsemolytic group. 



On the whole, there may be said to be substantial agreement 

 in the results of those who have systematically used fermentation 

 tests. In the description of any strain these should be taken 

 along with other characters— morphology, growth conditions, 

 pathogenicity, hsemolytic and fermentative effects, solubility or 

 non-solubility in bile-salts, etc. 



At present no definite opinion can be expressed as to the 

 etiological relation of streptococci to scarlet fever ; we can 

 only say that streptococci are almost invariably present in the 

 fauces, and that to them many of the complications of the disease 

 are due. The streptococcus conglomeratus (anginosus) is speci- 

 ally abundant as a rule, though it also occurs in other acute 

 catarrhal states. In fact, Gordon found that the types of strepto- 

 cocci in the throat in scarlet fever corresponded with those met 

 with in normal conditions. Mair has recently isolated an organism 

 to which he has given the name diplococcus scarlatina; he 

 obtained it from the' throat in over 80 per cent, of cases of scarlet 

 fever. It is an oval coccus occurring usually in pairs like the 

 pneumocoecus, and, as it is soluble in bile salts and ferments 

 inulin, is, rather to be classified with that organism. Most strains 

 fail to grow on agar or in bouillon' without the presence of serum.- 

 Prom experiments on monkeys and on other grounds he considers 

 that it probably has an etiological relationship to the disease. 



Bnterococcus. — This variety, when growing in the tissues, usually 

 occurs as a diplococcus, the individual organisms being rounded or oval, 

 and the members of a pair being often set at an angle, and unequal in 

 size ; sometimes there is indication of a capsule. In cultures it shows 

 considerable pleomorphism, and tends to grow in masses, though short 



