In gymnosperms, ......... lacks .... canal cells.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what type of canal cells are lacking in gymnosperms.

2. **Identifying the Relevant Structure**: The canal cells in question are found in the archegonium, which is the female reproductive structure in certain plants, including gymnosperms.

3. **Describing the Archegonium**: The archegonium is a flask-shaped structure that consists of a neck and a base. The neck contains canal cells, while the base houses the egg cell.

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