Asterias
Antedon
Echinus
Ophiothrix
B. Antedon
Asterias
Antedon
Echinus
Ophiothrix
Sea cucumber
Sea lily
Sea urchin
Sea star
Sea hares
Brittle stars
Star fishes
Sea fish
mouth apparatus
exoskeleton
skeletal system
bioluminscent organ
pluteus
echinopluteus
bipinnaria
auricularia
movable
immovable
prehensile
all of these
number of arms
structure of the ambulacral groove
tube feet
pedicellariae
haemal system
digestive system
ambulacral system
reproductive system
Nervous system with a large brain
Respiratory system
System of internal seleton
Excretory system
Crinoidea
Asteroidea
Holothuroidea
Ophiuroidea
Sand dollar
Jelly fish
Silver fish
All of these
Crinoidea
Asteroidea
Holothuroidea
Ophiuroidea
torneria
onchosphere
trochophore
bipinnaria
locomotion
respiration
feeding
all of these
digestive system
water vascular system
canal system
none of these
tube feet
lobopodia
cephalopodia
rhizopodia
sea-hares
sea-stars
devil fish
sea fans
Asteroidea
Crinoidea
Ophiuroidea
Holothuroidea
excretion
absorption
reproduction
respiration
herbivorous
omnivorous
carnivorous
none of these
coelenterates
marine arthropods
echinodermates
sponges
Sea-star
Star fish
Sea-cucumber
Sea lily
Starfish
Jellyfish
Cuttlefish
Fresh water mussel
Sea stars
Cake urchins
Sea lilies
Sea cucumbers
Schizocoelic coelom
Water vascular system
Spines in the body mass
Marine habitat
echinodea
holothuroidea
asteroidea
ophiuroidea
Sea cucumber
Brittle star
Feather star
Both (b) and (c)
ctenidia
dermal branchiae
book lungs
trachea
Holothuria (sea cucumber)
Echinus (sea urchin)
Echittocardium (sand dollar)
Antedon (feather star)
an exoskeleton
a spiny skin
bilateral symmetry
gastrovascular cavity