Hayes Common, William Henry Millais
In the collection of the Yale Center for British Art, which has both zoomable and downloadable files. There is also a zoomable file on Google Art Project, and a downloadable file of that image, which is slightly larger and more colorful, on Wikimedia Commons.
William Henry Millais, the elder brother of John Everett Millais, and also part of the Pre-Raphaelite Brotherhood, was known for his paintings in watercolor and gouache.
The center’s website lists the medium for this work as “oil on canvas”, but I think that’s a mislabeling.