Ceriantharia
50
have light organs. Examples: Loligo, Sepia, Octopus and Nautilus. Although
there are at present still several hundreds of species, their peak development
was during the Mesozoic. There are 7500 fossil species (cephalopod shells),
e.g., the well-known ammonites.
Ceriantharia order of the subclass Zoantharia, class Anthozoa (phylum Cnidaria).
Anemone-like anthozoans with a large number of long slender tentacles in
two series. The body is elongated and adapted for living in sand or mud in
self-secreted felt-like tubes. On disturbance the animal retracts very quickly.
Cestoda (tapeworms) class of the phylum Platyhelminthes. Parasitic flatworms, in
which the gut is absent. Most adults live in the intestines of terrestrial, freshwater or marine vertebrates. Larval stages develop within an intermediate
host. An example is the pork tapeworm (Taenia solium).
Cetacea (cetaceans) --7mammals, marine.
Chaetognatha (chaetognaths, arrow worms) phylum. Elongated (to a few cm),
transparent, unsegmented coelomate (with coelom) animals with a marked
head, trunk, and tail. The head bears eyes, chitinous spines, and jaws. The
trunk and tail have lateral and caudal fins. The alimentary canal is straight
and simple, there is no special excretory, respiratory, or vascular system.
Arrow worms are cross-fertilizing hermaphrodites without larval stage. They
Eyw
Hood _ _ "::;;~!lfj~- r .. _
Chaetognatha. (Barnes 1987)
50
have light organs. Examples: Loligo, Sepia, Octopus and Nautilus. Although
there are at present still several hundreds of species, their peak development
was during the Mesozoic. There are 7500 fossil species (cephalopod shells),
e.g., the well-known ammonites.
Ceriantharia order of the subclass Zoantharia, class Anthozoa (phylum Cnidaria).
Anemone-like anthozoans with a large number of long slender tentacles in
two series. The body is elongated and adapted for living in sand or mud in
self-secreted felt-like tubes. On disturbance the animal retracts very quickly.
Cestoda (tapeworms) class of the phylum Platyhelminthes. Parasitic flatworms, in
which the gut is absent. Most adults live in the intestines of terrestrial, freshwater or marine vertebrates. Larval stages develop within an intermediate
host. An example is the pork tapeworm (Taenia solium).
Cetacea (cetaceans) --7mammals, marine.
Chaetognatha (chaetognaths, arrow worms) phylum. Elongated (to a few cm),
transparent, unsegmented coelomate (with coelom) animals with a marked
head, trunk, and tail. The head bears eyes, chitinous spines, and jaws. The
trunk and tail have lateral and caudal fins. The alimentary canal is straight
and simple, there is no special excretory, respiratory, or vascular system.
Arrow worms are cross-fertilizing hermaphrodites without larval stage. They
Eyw
Hood _ _ "::;;~!lfj~- r .. _
Chaetognatha. (Barnes 1987)