140 



62 



Nos. 19 and 20 are particularly interesting, having been isolated from fæces which were 

 extracted with due precautions as to sterility from the rectum of a blue fox and a seal 

 (Phoca foetida) in the extreme north of Greenland, at a spot where infection from without 

 Would be most unlikely to take place i). .Sc. fæciuin must therefore be one of the commonest 

 intestinal bacteria among animals. It has a high power of resistance, and not a single one 

 of the strains has died out under our hands during the years We have had them. It is also 

 fairly omnivorous, and can grow at widely different temperatures, so that it should be 

 able to thrive practically everywhere throughout the World. 



It can stand heating to 70° — 75°. All strains develop at 10°, and some even at 5°. 

 It exhibits lively growth right up to 50°. Exceptions are the two strains (17 and 18) with 

 slight fermentation of arabinose, which do not thrive over 47 14°. Owing to its good growth 

 at 40° — 50°, it may be found in milk Which has been kept at high tempeiatures, as with 

 Nos. 7, 8 and 18. For the same reason, it is found in vegetable matter stored warmly 

 in pits, as Nos. 9 and 10, which were found in boiled potatoes which had soured spontane- 

 ously. 



Streptococcus fæciuin grows rapidly in broth, but comparatively slowly in milk and 

 never attacks casein to any considerable degree. It always ferments arabinose, but only 

 exceptionally (Nos. 11, 12 and 19) any great quantity of xylose. It generally ferments 

 mannite and saccharose, but in respect of this faculty, fluctuations may be observed even 

 in one and the same strain. No. 1, for instance, on the first investigation, fermented sac- 

 charose, and No. 15 mannite, but by the very next investigation, they had permanently 

 lost this power. In their relation to the sugars, the non-saccharose-fermenting strains 

 resemble Streptococcus lactis. Nos. 1 — 4 ferment sorbite, and are thus nearer the species 

 next following, .Sc. glijcerinaceus, Sc. fæcium often ferments rhamnose and raffinose, but 

 in this respect. We may also find differences within one and the same strain. The present 

 species is thus characterised by a comparatively wide range of variation, and it is there- 

 fore not remarkable that strains of the same origin (Nos. 2, 3, 5, 13 and 15) should exhi- 

 bit such dilTerences in respect of fermentation power as shown in the table. 



Streptococcus fæcium is a pronounced diplococcus, (PI. XV — XVI) which does not as 

 a rule stretch before division, and may therefore — especially on solid substrates — 

 present a micrococcus-like impression. Even in broth, it only forms very short chains. 

 Some few strains (6 and 12) can form elongated cells on AG. 



Streptococcus glycerinaceus (Table XXI). I have named it from its remarkably 

 powerful fermentation of glycerin. The few strains which We have succeeded in isolating 

 were all with one exception derived from cheese. As it grows, in contrast to most true 

 lactic acid bacteria, equally well on AG and SG, its presence in a substance is most easily 

 discerned by sjjreading a little on AG. In stab cultures, it exhibits a somewhat stronger 

 leiideiicy to surface growth than the other lactic acid bacteria. L\kc Streptococcus fæcium, 

 it can often stand heating to 70° — 75°. It grows between 10°— 45°, and two of them (6 and 

 7) even developed at 50°. 



') These strains arise from an expedition of Knud Rasmussen. The samples of fæces were taken 

 by the Swedish botanist, the late Dr. Thorild Wulff, and sent to Prof, Babthei, in Stockholm for a 

 complete bacteriological investigation. The isolated lactic acid bacteria were further sent to me to be 

 exactly identified. 



