Ward. — Some Thames Bacteria. 291 
twenty-four hours, and subsequently a few bubbles formed, 
and granular flocks were deposited. No definite turbidity, 
and no increase in three weeks. 
The most likely form I have been able to trace resemblances 
to is Jaksch’s Bacterium ureae , which may be distinct, as he 
believes it is, from Pasteur and Van Tieghem’s Micrococcus 
ureae. 
It agrees with Jaksch’s form in the size of the rodlets, the 
general characters of the plate cultures, and particularly in 
the dull (matt), ground-glass appearance. The stab-cultures 
also agree fairly well, though I have never detected the smell 
of ‘ Haringslake ’ noted by Jaksch. 
The growth is described as ‘ ungemein langsam V Of course 
this is very indefinite : in my form the growth is slow but not 
uncommonly so. The general behaviour as to temperature 
agrees, so far as can be gathered from the meagre information 
to hand. 
I prepared tubes of Jaksch’s fluid as follows — per 1 litre 
water : — 
iV gram. 
Mg S 0 4 . 
1 
8 » 
. 
. . K H 2 P 0 4 . 
5 * 
. 
. . Rochelle Salt. 
5 „ 
. 
. . Urea. 
In this perfectly clear liquid the organism grew very slowly, 
forming grease-like flecks and films on the surface and a very 
white deposit. Better at 25 0 than at 35 0 . No odour could 
be detected, and it is pretty evident that if this is Jaksch’s 
form, it grows but feebly in the liquid given. 
M. ureae seems to differ from the rodlets chiefly in growing 
more quickly and at higher temperatures, and in the cocci — 
which may also be in pairs or tetrads or chains — and in the 
occasional formation of zoogloea. 
The stearine-like plate-cultures are very suggestive, and 
the stab-cultures agree well, except that I have not noticed the 
odour described. 
1 Zeitschr. f. Phys. Chemie, Bd. 5, p. 395. 
