This is a rare English Porcelain Teapot, circa 1825, made by Zachariah Boyle & Sons of Stoke, Staffordshire. The chinoiserie pattern is identified as "Boy in Door" on page 53 of the book "Chinoiserie..." by Howard Davis.
For other examples of this shape by Zachariah Boyle, see plates 1557, 1559, and 1560 of "A Directory of British Teapots" by Berthoud and Miller.
I've shown the strainer for you: it has 20 holes in a triangular shape.
Although this early teapot has many condition problems, it displays nicely. It should appeal to the advanced collector of early 19th C English porcelains or chinoiserie patterns as a study piece.
Condition: 1. There is a chip to the underside of the shoulder or collar. 2. There is a very well done repair to the spout (which was difficult to photograph. 3. There is a small crack at the base of the handle. (The pot should not be carried by the handle.) 4. There is a discolored line under the spout which cannot be felt as a crack, and does not go through to the interior. 5. There are some light brown spots in one place on the top of the collar or shoulder.
The teapot is unmarked.