MXieuicanJAuscum - American Museum of Natural History

1959 SQUIRES: ATLANTIC CORALS
3
"Challenger," "Thor," "Valdivia," and "Porcupine" and the several
voyages under the sponsorship of Prince Albert I of Monaco are responsible
for our knowledge of the types and distribution of the coral
fauna. Regional collecting is often of greater significance, for these
operations are frequently more intensive. Notable are the collections
of the various United States Coast and Geodetic Survey vessels in the
Caribbean and western Atlantic region recorded by Pourtales, Agassiz,
and others. Characteristic of much of this older work (large-scale dredging
operations have not been carried out for several decades) is a tendency
to separate morphologic variants into species, which has resulted
in a plethora of names. Some of the earlier works are also marred by
poor illustrations (by modern standards) and inadequate descriptions.
The term "deep-sea" used in this study refers to the most general
connotations of the phrase, particularly as encountered in some of the
coral literature. According to the system given by Hedgepeth (1957),
all but three of the stations are bathyal, the exceptions being from "sublittoral"
depths but isolated from the continental shelf and directly
related to bathyal forms. The major division of corals into hermatypic
and ahermatypic (Wells, 1933, p. 109) refers to the biologic division
between reef-forming and non-reef-forming corals. Included within
the ahermatypic group are a large number of genera of often diverse
ecologies. The important group of sublittoral rhizangiid corals is
placed there and is found in a much wider distribution than the hermatypic
corals, but is apparently restricted in depth distribution. A large
and diverse group of genera, including several discussed in this paper,
e.g., Dendrophyllia, is found associated with reefs both in shallow and
deep waters and ranges well outside the distribution of the hermatypic
corals. The remainder of the ahermatypic corals, including the majority
of genera discussed here, are deeper-water forms found in waters up
to 4000 meters but which may occur in shallower cold waters. These
then are the deep-sea corals, sometimes referred to as the simple corals.
This is a misnomer; for, although solitary forms are most frequently
encountered in deep waters, colonial forms are not absent.
Before any synthesis of the distribution of the deeper water faunas
can be made, together with interpretations of the causes and effects,
some pattern must be made of the occurrence of species. Although
many taxonomic characters of the Scleractinia are not adaptable to
mensuration, as many data as possible are recorded here for those
samples that warranted treatment. It is possible that the accumulation
of such data may give insight into the great population variability
observed for these corals.