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Work on Palaeozoic and
younger fish microfossils (now called variously
microvertebrates or ichthyoliths) is still
in its infancy. Although
even A
GASSIZ(1833-1844
a-b) studied microscopic fish remains, e.g. " Diplodus
minutus",
Ctenoptychiusin the
5-10mm range, it was not until the advent of better
microscopes in the late 19th
and 20th centuries that
systematic studies truly got under way. Early work
especially into histological
characteristics was
developed by W
ILLIAMSON(e.g.,
1849) and M
CCOY(1853).
However, the first notable
contribution by one who might be regarded as the father
of microichthyology was Christian
P
ANDERwho
with his prophetic work on
conodonts and fish in 1856 set the standard for later
works into both groups. There
followed useful work
including investigations by
R
OEMER(1885),
RÖSE(1898),
and ROHON(1890,
1893) in the Old World. In
the Americas, AGASSIZ's
student, Orestes St. J
OHNand
his amateur, turned professional, colleague
Amos Henry
WORTHENcontributed
significantly in the second half of the 19th century
(e.g., St. J
OHN&
W
ORTHEN1875).
The first half of the
20th century saw major contributions on particularly
thelodont and acanthodian scales by
B
ROTZEN(1934
a-b), HOPPE(1931),
LEHMAN(1937)
and especially Walter GROSS(1935,
1938). In North
America,basic research on
other microremains was begun by
HUSSAKOF&
BRYANT(1918),
Harold C. S TETSON
(1928, 1931), and
John WELLS(1944).
After the Second World War GROSSand
Tor ØRVIGset
the standard for
morphological and histological research approaches which
have become the basis for our studies
(GROSS1947-
1973,
ØRVIG1957-1980).
In North America Robert DENISONbegan
a research programme, sadly mostly
unpublished, to extract
microremains from rocks in the USA and Canada (e.g.,
DENISON1956,
1967, Field Museum
collection). A new generation of students following them
considered the biostratigraphical importance
of the microremains in more
detail, and mirroring some of the style of the conodont
work of the 1930s began to
look at associated assemblages and to employ element
taxonomies. Introduction of the use of the Scanning
Electron Microscope in the
late 1960s, the first use of which on fossil fish tissues
J
ANVIER(1996a)
ascribed to
G
ROSS(1968c),
was quickly taken up for studies on thelodont and shark
scales and teeth (e.g., TURNER1973,
A
NTIA&
W
HITAKER1978,
K
ARATAJUTE-TALIMAA1978).
SEM work has revolutionised the way we regard the
microornament and
ultrastructures of microvertebrate material and thus
increased the number of characters we
can use in defining and
relating taxa. The traditional binomial system or open
nomenclature has become the
preferred methodology compared to that espoused by later
"stratignathers" working mainly but not
whollyon
Tertiary remains (e.g.,
DOYLEet
al. 1974, TWAY1979),
who employed a descriptor or coded taxonomy.
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