|
(1) Mollusca |
Normally oviparous and development through a trochophore or veligerlarva |
|
(2) Arthropoda |
Body divided into head, thorax and abdomen and respiration by tracheae |
|
(3) Chordata |
Notochord at some stage and separate **** and urinary openings to the outside |
|
(4)Echinodermata |
Pentamerous radial symmetry and mostly internal fertilization |
