198 
Ward . — Thames Bacteria , III. 
As will be shown below, some very remarkable biological 
characteristics have been determined for this type, which 
would doubtless repay more prolonged and closer study than 
I have accorded them. 
That this type is related to a whole series of yellow pig- 
mented Bacteria on the one hand, and of powerfully liquefying 
non-pigmented forms on the other, is rendered probable from 
the following results. 
Group VI. 
The Proteus Type. 
Nos. 103, 34, 51, 61, 9, 9 a, l , </>, and 6 . 
In the present section I bring together a series of forms 
which include some ‘ species ’ already well known to water- 
bacteriologists, and best typified by Proteus vulgaris and its 
allies. Several authorities have already disagreed as to how 
far these do or do not liquefy gelatine — my studies lead to 
the conviction that the power of liquefaction varies with the 
conditions, both external and internal. 
In his remarkable book entitled ‘ Ueber Faulnissbakterien 1 ’ 
Hauser published in 1885 the results of his investigations 
into the bacteriology of three forms or species of Proteus , 
as he named them : these are P. vidgaris , P. mirabilis , and 
P. Zenkeri. Various criticisms have been directed against 
Hauser’s naming of this new genus, and many observers have 
refused to take these forms out of the genus Bacilltis on the 
evidence adduced : I do not propose to discuss this, merely 
remarking that the genus Bacillus , as at present defined, 
should depend on the formation of endogenous spores in the 
rodlets, whereas the literature teems with so-called species 
of Bacillus , in which no such spores have been observed. 
In any case Hauser seems to have hit on a good name, for 
the forms are evidently eminently protean in character, so 
far as peculiarities of colonies go. 
1 Leipzig, 1885, F. C. W. Vogel. 
