134
ROBINA B. SCHOLES AND J. M. SHEWAN
interest. As on land, many ecological situations arise which are at
present very imperfectly understood. The interrelationship of bacteria,
yeasts, moulds and fungi to phyto- and zoo-plankton and to higher
plants and animals, involving symbiotic, antibiotic and other effects
can only vaguely be guessed at (see Wood, 1968'; Nigrelli, 1962;
Sieburth and Pratt, 1962). Moreover, the vast potential of marine
microorganisms in the industrial field, as sources of enzymes or of new
antibiotics for instance, can only be dimly apprehended.
In this review it is obviously not possible to cover all aspects of
marine microbiology. This would require a book by a team of specialists
rather than a single chapter. m7e therefore propose to confine ourselves
mainly to those aspects of the subject with which we have had some
experience or of which we have some knowledge.
11. SAMPLING TECHNIQUES
As with every natural environment sampling involves difficulties
both in apparatus and, if culturing is also involved, in the conditions of
sampling and in the media to be employed.
A. Use of containers
For the sampling of sea water at various depths a variety of instruments have been proposed (ZoBell, 1946). The most effective over the
years has been that of ZoBell (1946) or its modifications, in which the
sea water is collected in sterile stout-walled glass containers at the
appropriate depth. Many such containers can be strung along a hydrological cable and, at the desired depths, filling is accomplished by a
trigger mechanism, releasing a weighted messenger which, as it descends,
breaks in turn the sealed glass tubes leading to each sterile container.
Metal containers made of, say, copper or bronze are known to
exert considerable bacteriostatic or bacteriocidal effects on many
strains of marine bacteria and consequently are not to be recommended
(ZoBell, 1946). However, Kriss (1963) has recently suggested that
metal bathometers can be used satisfactorily if the sample is not too
long in contact with the metal surfaces. ZoBell (1946, 1963) doubts
this, pointing out that it is contrary to all previous experience, particularly accurate quantitative work. Sorokin (1962) has recently published
comparative figures of the saprophytic population at the same station
and depth, after sampling with a non-sterile metal bathometer as advocated by Kriss and with a specially designed sterile sampler. The results
given in Table I show the discrepancies likely to arise by the use of
non-sterile bathometers. Another water sampler has recently been
introduced (Niskin, 1962) which is said to give excellent results (Kirtley,
ROBINA B. SCHOLES AND J. M. SHEWAN
interest. As on land, many ecological situations arise which are at
present very imperfectly understood. The interrelationship of bacteria,
yeasts, moulds and fungi to phyto- and zoo-plankton and to higher
plants and animals, involving symbiotic, antibiotic and other effects
can only vaguely be guessed at (see Wood, 1968'; Nigrelli, 1962;
Sieburth and Pratt, 1962). Moreover, the vast potential of marine
microorganisms in the industrial field, as sources of enzymes or of new
antibiotics for instance, can only be dimly apprehended.
In this review it is obviously not possible to cover all aspects of
marine microbiology. This would require a book by a team of specialists
rather than a single chapter. m7e therefore propose to confine ourselves
mainly to those aspects of the subject with which we have had some
experience or of which we have some knowledge.
11. SAMPLING TECHNIQUES
As with every natural environment sampling involves difficulties
both in apparatus and, if culturing is also involved, in the conditions of
sampling and in the media to be employed.
A. Use of containers
For the sampling of sea water at various depths a variety of instruments have been proposed (ZoBell, 1946). The most effective over the
years has been that of ZoBell (1946) or its modifications, in which the
sea water is collected in sterile stout-walled glass containers at the
appropriate depth. Many such containers can be strung along a hydrological cable and, at the desired depths, filling is accomplished by a
trigger mechanism, releasing a weighted messenger which, as it descends,
breaks in turn the sealed glass tubes leading to each sterile container.
Metal containers made of, say, copper or bronze are known to
exert considerable bacteriostatic or bacteriocidal effects on many
strains of marine bacteria and consequently are not to be recommended
(ZoBell, 1946). However, Kriss (1963) has recently suggested that
metal bathometers can be used satisfactorily if the sample is not too
long in contact with the metal surfaces. ZoBell (1946, 1963) doubts
this, pointing out that it is contrary to all previous experience, particularly accurate quantitative work. Sorokin (1962) has recently published
comparative figures of the saprophytic population at the same station
and depth, after sampling with a non-sterile metal bathometer as advocated by Kriss and with a specially designed sterile sampler. The results
given in Table I show the discrepancies likely to arise by the use of
non-sterile bathometers. Another water sampler has recently been
introduced (Niskin, 1962) which is said to give excellent results (Kirtley,