Roy J. Snell (1878-1959) authored at least 85 Young Adult novels under his own name and as by David O\'Hara, James Craig, and Joseph Marino, most of them specifically directed to boys, though he wrote at least one series of mysteries for girls. His tales for younger children, beginning with Little White Fox and his Arctic Friends (1916), are animal Fantasies.
Mockingbird Songs
Slenderman (Emma Frost Book 9)
Leaving Everything Most Loved
Swimming to Catalina (Stone Barrington 4)
Blue Monday
The Hunchback of Westminster
The Breach
Saving Ferris