292 
Ward.— Some Thames Bacteria . 
In both cases we are devoid of information as to the 
behaviour in other media than gelatine and urine or Jaksch’s 
fluid, so that it is impossible to be sure of the identity of 
these forms. 
There are some distinct resemblances also to Zimmermann’s 
M. concentricus 1 , but he does not note the dull stearine-like 
appearance which is so striking in all my cultures. 
As Tatarofif 2 himself remarks, his ‘ Perlmutter-glanzende 
Diplococcus’ may be M. ureae , and the resemblances are 
noted. 
The following tabular summary gives the salient characters 
of this Bacterium. 
Habitat. 
Morphological 
characters. 
Plates. 
Stab. 
Streak. 
Agar. 
Potato. 
Broth. 
Milk. 
Glucose. 
Urine. 
Not uncommon in the Thames. 
Cocci about 1 n, not motile, single or grouped in pairs, rows 
of four, or in heaps, and formed by breaking up of rodlets 
2 x 1 At. 
At 1 2-1 5 0 C. forms slowly growing white, typhoid-like, irregularly- 
circular, contoured, zoned, and radially-marked fronds : edges 
hyaline, centre yellowish. Become dull, matt, and like thin 
stearine drops. 
1 2-1 5 0 yellowish white dots in the tunnel, and a thin frond-like 
ground-glass above. This is hard and tough, and matt, as 
in plate colonies. Quicker at 20-2 2 0 C. 
At 20 0 grow fairly rapidly as a white, thin, matt film, nearly 
covering the whole surface in a week. The streak thicker. 
At 30-35° grows slowly as a dull white and dryish layer. At 
22° the characteristic white waxy matt film forms more 
rapidly. In some cultures isolated colonies form on the 
surface and coalesce to form the film, as polygonal Turbot- 
scale-like mosaic. 
No growth at 34° At 22° a dull, yellowish-white, waxy, dry 
streak-like stearine, darkening to buff, and after some weeks 
to umber. 
At 25° forms dense floating flecks and greasy white films, which 
fall as an abundant deposit, eventually buff- white. The 
films are renewed and liquid remains nearly clear. The greasy 
films adhere to sides of tube above. 
No change at 25° beyond acid reaction. 
No turbidity, but white veils and flocks form and fall as in broth, 
but less abundant. Better at 25° than 30°. 
At 25-30° a few bubbles and granular flocks only, and only slight 
traces of turbidity. 
1 Die Bakterien unserer Trink- und Nutzwasser, Chemnitz, 1890, p. 86. 
2 Die Dorpater Wasserbacterien, 1891, p. 71. 
