Pet Lamb Stories by Mrs. Harriet Myrtle

Published by Sheldon and Company
1. Pet Lamb
2. Bertha and the Bird
3. Duck House
4. Eggs and Chickens
5. Christmas Eve at the Cottage
6. Day in the Woods
7. Two Dear Friends
8. Scene in Spring
8a. By 1866, this book was "Going to the Cottage"
9. Goat and Her Kid
10. May Day at the Cottage
11. Little Amy's Birthday
12. Adventure of a Kite

These twelve books make up the Rose Bud Stories. They were sold as a 12 volume boxed set.
The books were also split up such that the first six titles were sold together as a boxed set called the Pet Lamb Series.

The second six (#7-12) were sold together as a boxed set called Little Amy’s Stories.

All twelve titles were copyrighted in 1866. Subsequently they were reprinted a number of times. (known editions in 1866, 1869 , 1870, 1871, and 1872) )

I suspect that the format changed in 1872 similar to the Violet Series.

Cloth. Various colors. Gilt spine. 4.5" x 3".
1869 boxed set of the Pet Lamb Series is shown below.

This format was used between 1866-1869.

1870

1871