Enlist four peculiar characters of coelenterata.

Explanation

### Step-by-Step Solution:

1. **Nidoblasts**: One of the peculiar characters of Coelenterata (Cnidaria) is the presence of specialized cells called nidoblasts. These cells are responsible for the movement of water within the organism and play a crucial role in the functioning of their body.

2. **Gastrovascular Cavity**: Coelenterates possess a prominent gastrovascular cavity. This cavity serves multiple functions, including digestion and respiration, allowing these processes to occur in the same structure, which is a unique characteristic of this phylum.

3. **Tissue Organization**: Coelenterates exhibit a tissue-level organization. Their body is composed of specialized tissues, including nidoblast cells and those forming the gastrovascular cavity. This level of organization is more complex than that of simpler organisms.

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