Quadragenarious

[…]cutting out valiantly from under the guns of a dozen rivals some stout buxom widow suited to his estate and to his medium years — one of those plumply mellow quadrigenarious bodies who especially appeal to the vigorous and well-salted emotion which with sailor-men stands for love[…]

This is doubtless the reason who^([sic]) our quadragenarious friends sometimes surprise us with their matrimonial ventures.

He signed the letter "Canis Quadragenarious" (Forty-year-old Dog).