178
A. D. BONEY
attachment. Taneka (1957) noted that a denser growth of Conchocelisfilaments occurred on the hinge side of the oyster shell.
Information is also available on the conditions which influence
growth and development of the filaments within the shell matrix.
Despite the earlier statement that growth of the filaments appeared
not to be affected by lowering of salinity, a number of workers have
produced evidence that changes in salinity can influence both elongationandbranching of the filaments (Saito, 1956b ; Yamasaki et al., 1957 ;
Ogata, 1960b, 1961). Thus the growth rate of the aaments was halved
when the salinity was reduced by the same amount ; whilst the I' taproot '' filaments were less affected, their growth was inhibited by any
further fall in salinity. Tetrazolium salts have been used as indicators
of the viability of filaments in the shells under test conditions (Ogata,
1956a,b).
Direct exposure to sunlight and severe desiccation rapidly killed the
Conchocelis filaments within the shells (Saito, 1956), and growth was
totally inhibited when shells were buried in the sand. Takeuchi et al.
(1956b) found that, together with exposure to direct insolation, subjecting the shells to air of low humidity and to high temperatures in shallow
water also rapidly killed the filaments. Observations on the pigmentation and metabolism of the Conchocelis filaments under different
environmental conditions have also been made (Sano, 1960). Ogata
(1960b) found that the compensation point for the Glaments lay between light intensities of 5-50 lux. An earlier observation by Ogata
(1 960a) indicated that vertical growth of the filaments ceased at 5 lux,
and was most rapid at 2000 lux. The general features of the metabolism
of the Conchocelis filaments were identical with those of Porphyra.
When the filaments were grown on glass slides development was enhanced by the addition of HC0,- to the culture medium, whereas
addition of calcium had little effect; variation in pH was ineffectual.
Little significant effect on growth of the filaments within the shell was
observed after addition of bicarbonate, phosphate, nitrate or ammonium salts to the culture medium (Ogata, 1961). The pH of the cell
contents was found to lie between values of 5 and 6, and passage of the
filaments through the calcareous matrices of the shell could be brought
about by the secretion of extracellular products of this pH. When
carpospores are germinated on the shell in a medium rich in bicarbonate
the developing filaments tend to grow on the shell surface, indicating
that availability of CO, could be a factor conditioning growth within
the shell. An interesting observation by Ogata (1961) showed that
filaments continued to grow within the matrix even when the shells
were immersed in liquid paraffin.
A. D. BONEY
attachment. Taneka (1957) noted that a denser growth of Conchocelisfilaments occurred on the hinge side of the oyster shell.
Information is also available on the conditions which influence
growth and development of the filaments within the shell matrix.
Despite the earlier statement that growth of the filaments appeared
not to be affected by lowering of salinity, a number of workers have
produced evidence that changes in salinity can influence both elongationandbranching of the filaments (Saito, 1956b ; Yamasaki et al., 1957 ;
Ogata, 1960b, 1961). Thus the growth rate of the aaments was halved
when the salinity was reduced by the same amount ; whilst the I' taproot '' filaments were less affected, their growth was inhibited by any
further fall in salinity. Tetrazolium salts have been used as indicators
of the viability of filaments in the shells under test conditions (Ogata,
1956a,b).
Direct exposure to sunlight and severe desiccation rapidly killed the
Conchocelis filaments within the shells (Saito, 1956), and growth was
totally inhibited when shells were buried in the sand. Takeuchi et al.
(1956b) found that, together with exposure to direct insolation, subjecting the shells to air of low humidity and to high temperatures in shallow
water also rapidly killed the filaments. Observations on the pigmentation and metabolism of the Conchocelis filaments under different
environmental conditions have also been made (Sano, 1960). Ogata
(1960b) found that the compensation point for the Glaments lay between light intensities of 5-50 lux. An earlier observation by Ogata
(1 960a) indicated that vertical growth of the filaments ceased at 5 lux,
and was most rapid at 2000 lux. The general features of the metabolism
of the Conchocelis filaments were identical with those of Porphyra.
When the filaments were grown on glass slides development was enhanced by the addition of HC0,- to the culture medium, whereas
addition of calcium had little effect; variation in pH was ineffectual.
Little significant effect on growth of the filaments within the shell was
observed after addition of bicarbonate, phosphate, nitrate or ammonium salts to the culture medium (Ogata, 1961). The pH of the cell
contents was found to lie between values of 5 and 6, and passage of the
filaments through the calcareous matrices of the shell could be brought
about by the secretion of extracellular products of this pH. When
carpospores are germinated on the shell in a medium rich in bicarbonate
the developing filaments tend to grow on the shell surface, indicating
that availability of CO, could be a factor conditioning growth within
the shell. An interesting observation by Ogata (1961) showed that
filaments continued to grow within the matrix even when the shells
were immersed in liquid paraffin.