Doherty's (Half Moon) Bay (Cal.) Express, partial strike of oval express company marking including an illustrated 'half-moon', used with pen-cancelled 3c Rose (65), perf flaws, possibly a replacement, on cover to Pescadero Cal., large area of cover behind stamp is neatly replaced with a cannibalized piece of backflap, still presentable, appears nearly fine, rare, the only recorded example, this small company is supposed to have operated between San Francisco and Half Moon Bay and Pescadero in 1865, partially illustrated in Nathan