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A. D. BONEY
are called " taneba ", and these are where the fixed spores and germlinge
appear in appreciable quantities in early autumn. The precise location
of the taneba shifts with the years, and the spore distribution appears
to be linked with the direction of the main surface current of a flood tide
(8egi and Kida, 1960). Iwanoto (1960) described four species of Monostroma which occurred in Tokyo Bay either as contaminants on Porphyra,
or as plants for cultivation. Monostroma tubuliforme favours regions
with lowered salinity, and grows from autumn to spring ; M . crmsissimum and M . Eatissimum appear at about the same time, whereas M .
grewillei grows over a much shorter period between December and March.
The four species show distinct morphological characteristics. M . nitidum
is collected for food in China. Life history studies on Monostromu have
been carried out by Yamada and Tatewaki (1959) and by Kornmann
(1962). As with the related genera, motile zygotes and zoospores are
the main means of dispersal.
Ulwa plants are more frequently used as food than Enteromorpha,
and the species Ulva lactuca and U. pertusa are the two plants
mainly used. Life histories have been studied in both instances, and an
isomorphic alternation of diploid and haploid plants is observed, the
diploid plants liberating quadriflagellate zoospores which give rise to
gametophytes on germination. The gametophytes produce biflagellate
gametes of different strain. The two genera appear in considerable
numbers in intertidal habitats, and are not cultivated on special " hibi ''
like Monostroma. The conditions which govern zooid discharge are of
interest, and the several factors involved here have been recently
summarized by Lersten and Voth (1960). Christie and Evans (1962) in
studies on the periodicity of zoospore and gamete release by Enterommpha intestinalis in the British Isles, observed that maximum
emission was obtained 3-5 days prior to the highest tide of each lunar
month. Conditions of light, temperature and salinity were also
important. Lersten and Voth (1960) emphasized the light dependence
of zooid discharge in Enteromorpha. Data of this nature would be of
importance in planning times of spore settlement should cultivation be
envisaged.
F0yn (1955) investigated " southern " and " northern " plants
of the ubiquitous Ulva lactuca, enquiring into their morphological
features and the environmental conditions governing growth, and
making crossing experiments between the gametes. From his observations F0yn concluded that the " southern " forms of the Ulwa lactuca
in fact constituted a distinct species which was called U. thureti.
This species was described as occurring on Mediterranean shores, and
on the Atlantic shores of Spain, Portugal and France.
A. D. BONEY
are called " taneba ", and these are where the fixed spores and germlinge
appear in appreciable quantities in early autumn. The precise location
of the taneba shifts with the years, and the spore distribution appears
to be linked with the direction of the main surface current of a flood tide
(8egi and Kida, 1960). Iwanoto (1960) described four species of Monostroma which occurred in Tokyo Bay either as contaminants on Porphyra,
or as plants for cultivation. Monostroma tubuliforme favours regions
with lowered salinity, and grows from autumn to spring ; M . crmsissimum and M . Eatissimum appear at about the same time, whereas M .
grewillei grows over a much shorter period between December and March.
The four species show distinct morphological characteristics. M . nitidum
is collected for food in China. Life history studies on Monostromu have
been carried out by Yamada and Tatewaki (1959) and by Kornmann
(1962). As with the related genera, motile zygotes and zoospores are
the main means of dispersal.
Ulwa plants are more frequently used as food than Enteromorpha,
and the species Ulva lactuca and U. pertusa are the two plants
mainly used. Life histories have been studied in both instances, and an
isomorphic alternation of diploid and haploid plants is observed, the
diploid plants liberating quadriflagellate zoospores which give rise to
gametophytes on germination. The gametophytes produce biflagellate
gametes of different strain. The two genera appear in considerable
numbers in intertidal habitats, and are not cultivated on special " hibi ''
like Monostroma. The conditions which govern zooid discharge are of
interest, and the several factors involved here have been recently
summarized by Lersten and Voth (1960). Christie and Evans (1962) in
studies on the periodicity of zoospore and gamete release by Enterommpha intestinalis in the British Isles, observed that maximum
emission was obtained 3-5 days prior to the highest tide of each lunar
month. Conditions of light, temperature and salinity were also
important. Lersten and Voth (1960) emphasized the light dependence
of zooid discharge in Enteromorpha. Data of this nature would be of
importance in planning times of spore settlement should cultivation be
envisaged.
F0yn (1955) investigated " southern " and " northern " plants
of the ubiquitous Ulva lactuca, enquiring into their morphological
features and the environmental conditions governing growth, and
making crossing experiments between the gametes. From his observations F0yn concluded that the " southern " forms of the Ulwa lactuca
in fact constituted a distinct species which was called U. thureti.
This species was described as occurring on Mediterranean shores, and
on the Atlantic shores of Spain, Portugal and France.