THE PRESENT STATUS OF SOME ASPECTS OF MARINE MICROBIOLOQY
169
ZoBell, C. E., arid Morita, It. (1957). Rarophilic bacteria in some deep-sea
sediments. J. Bact. 73, 563-68.
ZoBell, C. E., and Oppenheimer, C. (1850). Some effects of hydrostatic pressure
on tho multiplication arid morphology of ~narine bacteria. J . Bucl. 60, 77181.
ADDENDUM
Since this article was prepared for the press two important papers by
Sorokin (19G4a nnd b) have appeared which confirm the doubts expressed on
page 139 (linr 1) oosccrning the validity of some of the sampling techniques
employed by Kriss and his co-workers. Consequently the data and the
conclusions drawn therefrom may also be suspect. Briefly the more important
facts which liavc emerged may be summnrized as follows:
(1) Comparison of the results of the microbial analyses of parallel samples
obtnincd by the new sterile sampling technique of Sorokin and the nonstcrile Nansen-bottle method of Kriss has shown that the inside walls of the
Nansen bottles can be badly fouled Ijy Iictcrotrophic microorganisms which
contaminate tho water ,samplcu. Consecperitly the numbers of bacteria in
samples taken by the Nansen bottle arc as n rule several ordcrs of magnitude
grcater than tliosc tillrcn by the sterilc sampler.
(3) In thc Central Pacific area in which Sorokin worked, the vertical
distribution of hcterotrophs showed greatest numbers occurring near the
surfacc; in the cuphotir zone th(b numbers wcre more or less constant and
helow this zone a t a depth of 160 to 200 111 thrre was a decrease until a t
depths of 500 to 600 m and below bacteria were practically absent. These
data agrre with those of pmvioiis workers (summarized by ZoBell, 19463,
but are different, from those of Kriss (1063), obtained in the same region.
The latter sliowrd that in both thc. surfacc and deep waters hundreds of
thousands of heterotrophs per Born1 of water could be found. These
discrepancies Sorokin believes are due mainly to differences in the sampling
techniques.
(3) Sorokin also believes the submerged slide technique as used by Kriss
(1963) is subject to error and he has devised a new method using a special
stoppered cylindrical containcr for the slide. He suggests that the open slide
of Kriss in passing through the water column and the surface often becomes
contaminated by microorganisms and particles of animal tissue cut and disintegrated by the movement of the slide. Such animal debris when stained
rcscmbles bnctrria and as already mcntiond on page 143, line 33, and now
conhmcd, appears to explain the origin of the supposed new claw of hncteria,
h‘rnssilnikociae. set up by Kriss.
(4) If it can be assumcd that thr non-strrile Nansen bottle technique of
Giss is subject to a reasonably constant error’, at least so far as numbers are
conccrn~~l, then it may well be that thc broad concliisions d r a w from
comparisons of Kriss’ data given in Tables I1 and 111 (page 13!1 and 141
respectively) are still generally valid, e.g. that the numbers of heterotrophs
169
ZoBell, C. E., arid Morita, It. (1957). Rarophilic bacteria in some deep-sea
sediments. J. Bact. 73, 563-68.
ZoBell, C. E., and Oppenheimer, C. (1850). Some effects of hydrostatic pressure
on tho multiplication arid morphology of ~narine bacteria. J . Bucl. 60, 77181.
ADDENDUM
Since this article was prepared for the press two important papers by
Sorokin (19G4a nnd b) have appeared which confirm the doubts expressed on
page 139 (linr 1) oosccrning the validity of some of the sampling techniques
employed by Kriss and his co-workers. Consequently the data and the
conclusions drawn therefrom may also be suspect. Briefly the more important
facts which liavc emerged may be summnrized as follows:
(1) Comparison of the results of the microbial analyses of parallel samples
obtnincd by the new sterile sampling technique of Sorokin and the nonstcrile Nansen-bottle method of Kriss has shown that the inside walls of the
Nansen bottles can be badly fouled Ijy Iictcrotrophic microorganisms which
contaminate tho water ,samplcu. Consecperitly the numbers of bacteria in
samples taken by the Nansen bottle arc as n rule several ordcrs of magnitude
grcater than tliosc tillrcn by the sterilc sampler.
(3) In thc Central Pacific area in which Sorokin worked, the vertical
distribution of hcterotrophs showed greatest numbers occurring near the
surfacc; in the cuphotir zone th(b numbers wcre more or less constant and
helow this zone a t a depth of 160 to 200 111 thrre was a decrease until a t
depths of 500 to 600 m and below bacteria were practically absent. These
data agrre with those of pmvioiis workers (summarized by ZoBell, 19463,
but are different, from those of Kriss (1063), obtained in the same region.
The latter sliowrd that in both thc. surfacc and deep waters hundreds of
thousands of heterotrophs per Born1 of water could be found. These
discrepancies Sorokin believes are due mainly to differences in the sampling
techniques.
(3) Sorokin also believes the submerged slide technique as used by Kriss
(1963) is subject to error and he has devised a new method using a special
stoppered cylindrical containcr for the slide. He suggests that the open slide
of Kriss in passing through the water column and the surface often becomes
contaminated by microorganisms and particles of animal tissue cut and disintegrated by the movement of the slide. Such animal debris when stained
rcscmbles bnctrria and as already mcntiond on page 143, line 33, and now
conhmcd, appears to explain the origin of the supposed new claw of hncteria,
h‘rnssilnikociae. set up by Kriss.
(4) If it can be assumcd that thr non-strrile Nansen bottle technique of
Giss is subject to a reasonably constant error’, at least so far as numbers are
conccrn~~l, then it may well be that thc broad concliisions d r a w from
comparisons of Kriss’ data given in Tables I1 and 111 (page 13!1 and 141
respectively) are still generally valid, e.g. that the numbers of heterotrophs