In 1898, densely stained reticular structure near the nucleus in the nerve cell of owl was first observed by:

Answer

### Step-by-Step Solution:

1. **Identify the Year and Context**: The question specifies the year 1898 and refers to a discovery related to a structure near the nucleus in nerve cells of an owl.

2. **Recognize the Scientist**: The scientist associated with this discovery is Camillo Golgi. He was known for his work on the nervous system and cell structures.

3. **Describe the Structure Observed**: Golgi observed a densely stained reticular structure near the nucleus in the nerve cell, which he named the Golgi apparatus or Golgi body.

4. **Explain the Golgi Apparatus**: The Golgi apparatus consists of flattened membrane-bound sacs called cisternae. It has two distinct phases:
- **Cis Phase**: This is the receiving side where vesicles come in.
- **Trans Phase**: This is the shipping side where vesicles are released.

5. **Conclude the Answer**: Therefore, the answer to the question is Camillo Golgi.

### Final Answer:
In 1898, the densely stained reticular structure near the nucleus in the nerve cell of the owl was first observed by Camillo Golgi.

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