Each is a stylized nude drawing of a female body doing a particular stretch.
Drawn by Tonya, from Miss Lilyan Malmstead's book 'Awaken your Sleeping Beauty'
Each illustration has a printed inscription on the back associated with the stretch: e.g. 'Awaken the Beauty og the Thighs, Calves and Ankles'.
Each has a pencil/pen inscription with info on name of book, artist, year, and states the Miss Malmstead was the model.
Assuming these are from the book.
Each measures 13.5 X 18.5 cm, in nice condition.
The book description:
New York: E.P. Dutton. 1935. First edition. Small octavo. From the preface "The purpose of this book is to awaken the perfect self, which you really are, and to develop in you a new dimension-ERECTITUDE". Also, from the title page "Lengthen the line between the chin and the waist and you will lengthen your years". Uncommon title with lovely illustrations by Tonya.
There were 10 illustrations.