Sponges of the New Caledonian lagoon - IRD

incorrectly interchanged with the terms
"ectosomal" and "subectosomal spicules"
(cL accessory, principal spicules).
Axial canal or filament
Central lumen of a spicule, occupied in
life by an organic filament.
Axial construction
Skeletal organisation in which some
components are condensed to form a
dense central region.
Axial skeleton
Organic ancl!or inorganic skeleton found
in the centre or axis of the sponge
(cL extra-axial).
·axon
Designates the number of axes (suffix).
Bark
Outer layer of spongin fibres in
Dictyoceratid and verongiid sponges.
Basopinacocytes
Outer layer of epithelial cells covering
the basal surface, at the point of
contact with the substrate (cL exopinacocytes).
Benthic
Living on the bottom of the sea; 'benthos'
refers to life forms on the seabed.
Bifurcate
Divides into two forks.
Bioerosion
Chemical and physical degradation of
an inorganic or organic substrate
caused by an organism.
Bipocilli
Modified small chelae as found in
Jophon; with one discoid end and the
other with a toothed rim or end.
Birotula
A microsclere with a straight shaft and
umbrella-shaped ends.
Blastula larva
see Amphiblastula or Coeloblastula.
Body plan
Grade of construction of sponge body
based on the compleXity of the aquiferous
system and disposition of choanacyte
chambers with interconnecting
canals (see asconoid, syconoid, leuconoid,
aphodal, diplodal, prosodal); (not
to be confused with the terms body
shape or growth form).
Bud
An asexual reproductive propagule.
Calicle
Unit of body form in a sclerosponge.
Calthrops
Megasclere with four equal and symmetrical
rays emanating from a central
point.
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Glossory