The first is the frontispiece of
Dinah Maria Mulock Craik. John Halifax, gentleman. Thirty-First edition. London: Hurst and Blackett, publishers, . , 430p. 1 plate. (British Museum P & D 1996,1104.09) The frontispiece plate is entitled: “Ursula March”. It is signed: “J E Millais, A.R.A.” you can see Millais's monogram and the date "1861" on the bottom right hand corner.
The second example is the illustration by Millais on the title page of:
Defoe, Daniel. Robinson Crusoe. London and Cambridge: Macmillan and Co., 1866. xii, 607p. (British Museum P & D 1996,0406.77) The illustration on the title page is of Robinson Crusoe. It is signed with the monogram of John Everett Millais, and is dated “1862” underneath the monogram.