Answer:
Schizocoelom: It is present in the protostomes. The body cavity or coelom originates from the splitting of the mesoderm. One part attaches to ectoderm and the other surrounds the endoderm. The space between them develops into the coelom. The blastopore forms the mouth. Examples of schizocoelous animals are Annelida, Arthropoda and Mollusca. In Arthropoda and Mollusca the coelom is filled by blood and is known as Haemocoel.