l.; and to identify whether the observed changes correspond to the original definition of the term by Goebel (1900-1905), which implies substantial changes in the leaf form among different metamers
during plant development.
Thus, all stimuli were metamers
based on the International Commission on Illumination (CIE) 1931 2[degrees] Standard Observer (that is, colorimetric metamers
When the lighting is changed, the metamers
no longer match.
The CIE defines two samples as metamers
if their spectra are different in the visible region and have identical tristimulus values for a single condition of illuminating and viewing.
Perception of colour, metamers
and colour constancy
The involvement of half element is in agreement with the development of the embryonic myotomes, originating each vertebral element by the fusion of the posterior and anterior halves of the anterior and posterior metamers
, respectively (Grasse, 1958).
When in active phase, this meristem forms buds that will develop into new growth units composed of one or several metamers
(also called phytomers).
Research carried out over the last forty years (Judd, MacAdam, & Wyszecki, 1964; Lennie & D'Zmura, 1988; Maloney, 1986; Maloney & Wandell, 1986; Shaw, Westland, & Thompson, 1999) has shown that, in natural environments, these two factors have limited ranges of variation and, consequently, the number of possible metamers
is also limited.
are considered the spectrally different radiations that produce' the same colour' under' the same viewing conditions' for a particular creature.
Modular growth and form of corals: a matter of metamers
In all target species there was a positive relationship between specific petiole mass and leaf biomass within metamers
. The slope of this relationship did not vary among neighbor identities in Datura ([Alpha] = 0.05), and differences in the amount of leaf biomass being supported by different petioles explained a significant amount of the variance in specific petiole mass ([r.sup.2] = 0.82; significant at [Alpha] = 0.001).
(3)Whether a polymer (or racemates, metamers
, isomers, polymorphs, antimers, tautomers, etc.) should or should not be considered a separate substance is a question I cannot settle here (but see Timmermans ; van Brakel ).