9 
BACTERIA IN WATER. 639 
mann), Bacillus plicatus, Bacillus devorans (Zimmermann), Bacillus gracilis 
(Ziemormanin), Bacillin guttatus (Zimmermann), Bacillus implexus (Zim- 
mermann), Bacillus punctatus (Zimmermann), Bacillus radiatus aquatilis 
(Zimmermann), Bailie vermiculosus (Zimmermann), Bacillus constrictus 
(Zimmermann), Bacillus fluorescens aureus (Zimmermann), Bacillus fluo- 
rescens longus (Zimmermann), Bacillus fluorescens tenuis (Zimmermann), 
Bacillus fuscus (Zimmermann), Bacillus rubefaciens (Zimmermann), Bacil- 
lus subflavus (Zimmermann), Bacillus janthinus (Zopf), Bacillus mycoides 
(Fligge), Bacillus tremelloides (Tils), Bacillus cuticularis (Tils), Bacillus 
filiformis (Tils), Bacillus ubiquitus (Jordan), Bacillus circulans (Jordan), 
Bacillus superficialis (Jordan), Bacillus reticularis (Jordan), Bacillus ru- 
bescens (Jordan), Bacillus hyalinus (Jordan), Bacillus cloacee (Jordan), 
Bacillus delicatulus (Jordan), Bacillus violaceus laurentius (Jordan). 
PATHOGENIC BACILLI. 
Bacillus typhi abdominalis (Kberth, Gaftky), Bacillus erysipelatos suis 
(‘‘ Bacillus murisepticus,” Koch), Bacillus septicemiz hemorrhagice 
(‘‘ Bacillus cuniculicida,” Koch), Proteus vulgaris (Hauser), Proteus mira- 
bilis (Hauser), Bacillus canalis capsulatus (Mori), Bacillus canalis parvus 
(Mori), Spirillum cholerse Asiaticae (‘‘ Comma bacillus,” Koch), Bacillus coli 
communis (Escherich), Bacillus hydrophilus fuscus (Sanarelli), Bacillus 
venenosus (Vaughan), Bacillus venenosus brevis (Vaughan), Bacillus vene- 
nosus invisibilis (Vaughan), Bacillus venenosus liquefaciens (Vaughan). 
The following additional species are described by Zimmermann (1894) in 
his second publication (‘‘ Die Bakterien unserer ‘rink- und Nutzwasser”). 
Micrococcus candidus, Micrococcus coralloides, Streptococcus cinereus, Mi- 
crococcus sulphureus, Micrococcus galbanatus, Micrococcus erythromyxa, 
Sarcina flavea, Sarcina aurantiaca, Sarcina rosea. Bacillus ruber, Bacillus 
miniaceus, Bacillus mesentericus roseus, Bacillus carnosus, Bacillus chryso- 
loia, Bacillus multipediculus flavus, Bacillus villosus, Bacillus radiatus, 
Bacillus fluorescens albus, Bacillus viridans, Bacillus turcosa, Bacillus halans, 
Bacillus nacreaceus, Bacillus mirabilis, Bacillus umbilicatus, Bacillus lactis 
viscosus, Bacillus synxanthus, Bacillus sericeus, Bacillus minutus, Bacillus 
stellatus, Bacillus radicosus, Bacillus vernicosus, Bacillus mucosus, Bacillus 
centralis, Bacillus spumosus, Bacillus annulatus, Bacillus liquefaciens, Bacil- 
lus disciformans. 
The following spirilla and ‘‘vibrios” have also been found in water— 
chiefly in river water : : a ae 
Spirillum volutans, Spirillum sanguineum, Spirillum serpens, Vibrio ru- 
gula, Spirillum plicatile, Spirillum marinum (Russell). Spirillum cholerze 
Asiaticee, Spirillum of Rénon, Vibrio aquatilis (Gunther), Vibrio of Weibel, 
Vibrios of Bujwid (Bacillus choleroides a and 6), Vibrio of Litfler, Vibrios 
of Bonhoff, Vibrio of Blackstein, Vibrios of Sanarelli, Vibrios of Fischer, 
Vibrio Berolinensis, Vibrio Danubicus, Vibrio of Pfuhl (v. Metchnikovi 2). 
Several of the ‘‘ vibrios” in this list which have recently been obtained from 
river water in various parts of Europe are probably varieties of the cholera 
spirillum, 
ADDITIONAL NOTES UPON BACTERIA IN WATER. 
It is now generally recognized by bacteriologists that the potability of 
water is to be determined by an investigation relating to the presence or ab- 
sence of known pathogenic bacteria, rather than by an estimate of the num- 
ber of bacteria present in each cubic centimetre of the water under exami- 
nation. From asanitary point of view the most important of these pathogenic 
bacteria are the cholera spirillum and allied ‘‘ vibrios,” the bacilli of the ** ty- 
phoid group” (Bacillus typhi abdominalis and allied forms), the bacilli of 
the ‘‘colon group” (Bacillus coli communis with its varieties and similar 
bacilli of fecal origin). When one of these pathogenic bacilli is present in a 
