List two peculiar characters of prototharians.

Explanation

### Step-by-Step Solution:

1. **Understanding Prototherians**:
- Prototherians are a subclass of mammals, which distinguishes them from other mammals. They are unique in their reproductive and anatomical features.

2. **Identifying Peculiar Characters**:
- The first peculiar character of Prototherians is that they are **egg-laying mammals**. Unlike most mammals that give live birth, Prototherians lay eggs, which is a characteristic more commonly associated with reptiles.

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