This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Crataegus Jonesae Sarg. Bot. Gaz. 31: 14. 1901.
A shrub, or a tree, occasionally 200 high. Spines 2' or 3' long; leaves elliptic-ovate, acute or obtuse at the apex, cuneate, serrate with acute lobes, the tips of the lobes often reflexed, 1 1/2'-4' long, 1 1/4-3' wide, glabrous, except along the veins beneath; petioles 1'-2' long, glandless, slightly pubescent; flowers about 12" broad; calyx-lobes linear, acuminate; calyx villous, the lobes glabrous outside; stamens about 10; anthers large, pink; styles and nutlets 2 or 3; fruit short-ellipsoid to pyri-form, about 8" thick, slightly pubescent, bright carmine-red; flesh thick, yellow, calyx-lobes persistent.
Islands and coast of Maine from Portland to Pembroke, and inland at Skowhegan. June; fruit ripe September.
Crataegus Margaretta Ashe, Journ. E. Mitch. Soc. 16: 72.
A shrub or small tree, sometimes 25° high, with ascending branches forming a round crown. Spines 3/4'-1 1/2' long; leaves oblong-obovate or ovate, sometimes broadly so, 3/4'-2 1/2' long, 3/4'-1 1/2' wide, obtuse or acute at the apex, cuneate or rounded at the base, serrate or doubly serrate with 2 or 3 pairs of acute or obtuse lobes toward the apex, glabrous when mature, dark green above, membranous; corymbs slightly pubescent, becoming glabrous; flowers 7"-10" broad, calyx-lobes lanceolate, acuminate, slightly pubescent inside; stamens about 20; styles and nutlets 2 or 3; fruit dull rusty green, yellow or red, compressed-globose to short-ellipsoid, angular, 4"-8" thick, its flesh yellow, mealy, hard; calyx-lobes reflexed, deciduous.
Crataegus suborbiculata Sarg. Rhodora 3: 72. 1901. C. nitidula Sarg. Geol. Surv. Mich. 521. 1907. C. Saundersiana Sarg. Ont. Nat. Sci. Bull. 4: 66. 1908. C. Dewingii Sarg. Rep. N. Y. State Bot. 1907: 34. 1908.
A small tree, sometimes 200 high, with spreading branches and a broad crown. Spines 1 1/4'-2' long; leaves ovate-orbicular, impressed-veined and dull dark green above, glabrous, serrate or twice serrate, acute at the apex, broadly cuneate at the base, 3/4"-2 3/4' long, 3/4'-2 1/2' wide; corymbs glabrous; flowers about 10" broad; stamens about 20, the anthers rose; styles and nutlets 4 or 5; sepals slightly glandular-margined; fruit globose or compressed-globose, 5"-8" thick; dull green to scarlet; calyx-tube somewhat prominent.