=3. CRATAeGUS.= Thorn Apples. Red Haws.

Large shrubs or small trees, most at home in a limestone region. This genus has been studied a great deal in this country. Much work is still necessary in Indiana since there are a number of other species that belong in this range. The "k.n.o.b country" and southwestern Indiana are likely to produce the best results.

A. Leaves not deltoid-cordate; p.u.b.escent or glabrous.

I. Leaves broadest at the middle or apex, cuneate.

a. Leaves broadest towards the apex.

Leaves not impressed-veined above, shining I. Crus-galli.

1 C. Crus-galli.

Leaves impressed-veined above, dull. II. Punctatae.

Fruit glabrous; calyx lobes entire.

Fruit ellipsoidal; nutlets usually 3 or 4.

Leaves bright yellow-green, slightly impressed above; fruit ellipsoidal. 2 C. cuneiformis.

Leaves dull gray-green, strongly impressed-veined; fruit short ellipsoidal. 3 C. punctata.

Fruit globose. 4 C. Margaretta.

Fruit villous; calyx lobes glandular-serrate. 5 C. collina.

b. Leaves broadest at the middle.

Leaves impressed-veined; nutlets deeply pitted on inner face. III. Macracanthae.

Leaves dark green, glabrous and shining above, coriaceous.

Fruit sometimes 16 mm. (2/3 inch) thick; stamens usually 10; leaves and anthers large. 6 C. succulenta.

Fruit sometimes 12 mm. (1/2 inch) thick; stamens 15-20; leaves and anthers small. 7 C. neo-fluvialis.

Leaves gray-green, p.u.b.escent and dull above, subcoriaceous. 8 C. Calpodendron.

Leaves not impressed-veined; nutlets without pits.

Calyx glandular margined, fruit more than 8 mm. (1/8 inch) thick; leaves not trilobate. IV. Rotundifoliae.

9 C. chrysocarpa.

Calyx lobes not glandular margined; fruit 4-8 mm.

(1/16-1/8 inch thick); leaves often trilobate towards the apex. V. Virides.

Fruit bright red, glaucous, 4-6 mm. (1/6-1/4 inch) thick; leaves serrate. 10 C. viridis.

Fruit dull dark red, 6-8 mm.

(1/4-1/3 inch) thick; leaves coa.r.s.ely serrate. 11 C. nitida.

II. Leaves broadest at the base.

a. Leaves 1.5-6 cm. (1/2-2-1/2 inches) long and wide, membranaceous; calyx lobes usually entire.

Leaves yellow-green, often slightly p.u.b.escent; fruit soft at maturity. VI. Tenuifoliae.

Fruit ellipsoidal, ovoid or pyriform. 12 C. macrosperma.

Fruit compressed, globose or subglobose. 13 C. basilica.

Leaves blue-green, glabrous; fruit hard at maturity. VII. Pruinosae.

Leaves elliptic-ovate. 14 C. Jesupi.

Leaves usually cordate.

Fruit conspicuously angled, strongly pruinose. 15 C. rugosa.

Fruit without conspicuous angles, slightly pruinose. 16 C. filipes.

Leaves usually cuneate.

Leaves deltoid. 17 C. Gattingeri.

Leaves ovate. 18 C. pruinosa.

b. Leaves 3-10 cm. (1-4 inches) long and wide; calyx lobes usually serrate. VIII. Coccineae.

Mature leaves usually glabrous above; young foliage bronze-green; anthers pink.

Corymbs and fruit glabrous. 19 C. coccinioides.

Corymbs and fruit p.u.b.escent or tomentose. 20 C. coccinea.

Mature leaves tomentose above; young foliage yellow-green; anthers yellow. 21 C. mollis.

B. Leaves conspicuously deltoid-cordate. IX. Cordatae.

22 C. Phaenopyrum.

=1. Crataegus Crus-galli= Linnaeus. c.o.c.k-spur Thorn. Newcastle Thorn.

Plate 77. Bark dark gray, scaly; spines many, strong, straight, 3-18 cm.

(1-7 inches) long; leaves obovate to elliptical, 2-10 cm. (3/4-4 inches) long, 1-4 cm. (1/4-1-1/2 inches) wide, sharply serrate, except towards the base, acute or rounded at the apex, cuneate, dark green and shining above, coriaceous, glabrous or occasionally slightly p.u.b.escent; petioles slightly winged above, glandless, 1-2 cm. (3/8-3/4 inch) long; corymbs glabrous or occasionally p.u.b.escent, many flowered; flowers appear in May or June, about 1.5 cm. (2/3 inch) wide; stamens 10-20; anthers usually pink; calyx lobes lanceolate-ac.u.minate, entire; styles and nutlets usually 2; fruit ripens in October, ellipsoidal-ovoid to subglobose, about 1 cm. (3/8 inch) thick, greenish to red; flesh hard and dry, rather thin.

=Distribution.=--Northern New York to Ontario, eastern Kansas and south through western Connecticut to Georgia and Texas. Introduced near Montreal, about Lake Champlain and Nantucket Island. Well distributed in Indiana (but apparently more common in the southern part of the State).

A small tree, sometimes 10 m. (35 feet) high, with spreading branches and a broad crown; but often a large shrub. This is a variable species and has received many names.