Animals that do not have a notochord are called non-chordata. Non-chordata make up about 95–97% of the world’s population. The characteristics of non-cordata are –
1. Notochord absent.
2. Nerve cord is glandular, digitate and sterile
3. Hemoglobin is present in plasma.
4. Absent hepatic portal system.
5. Eyes are formed from the skin.
6. The circulatory system is dorsal.
7. Flowers and stems absent.
8. True tail and endoskeleton absent.
9. Appendages have more than two pairs.
10. The anus is not posterior to the tail.
11. Cardiac apparatus present or absent on surface of alimentary canal