294 . MALACEAE. Vol. II. 



6. CRATAEGUS L. Sp. PI. 475. 1753.* 

 Shrubs or small trees, usually spiny, with alternate, simple, petioled, usually lobed 

 leaves (those on the vegetative shoots generally of different shape than those of flowering 

 branches and more deeply cut), deciduous stipules, and white (rarely pink) terminal corymbose 

 flowers with early-deciduous bracts. Calyx-tube cup-shaped or campanulate, adnate to the 

 carpels, its limb 5-lobed. Petals S, spreading, rounded, inserted on the margin of the disk 

 in the throat of the calyx. Stamens 5-25, inserted in 1-3 series; filaments filiform; anthers 

 oblong,, white, yellow,- or red. Ovary inferior, or its summit free, 1-5-celled; styles 1-5, 

 separate, persistent, usually surrounded at the base by tomentum; stigmas terminal; ovules 

 1 in each carpel, or if 2, dissimilar. Pome small, yellow, red, or rarely blue or black, con- 

 taining i-S bony nutlets, each usually i-seeded. Seed erect, flattish, the testa membranaceous. 

 [Greek, strong, from the hardnfess and the toughness of the wood.] 



About 300 species, natives of the north temperate zone, the tablelands of Mexico and the 

 Andes ; the center of distribution is in the eastern United States. Type species : Crataegus Oxya- 

 cantha L. The genus has been of great taxOnomic interest for ten years, about looo species having 

 been described, from the United States, during that period. Data are fast accumulating tending 

 to show that many of these newly described species are hybrids. 



A. Leaves not deltoid-cordate, pubescent or glabrous. 



a. Leaves pubescent or glabrous, if pubescent on one side only, always so beneath; 

 thorns I'-y' long (C monogyna 3" long) ; fruit not black. 



* Petioles 14 inch or longer. 



1. Leaves not deeply cut. 



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

 Leaves broadest towards the apex. 



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



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



Leaves broadest at the middle. 

 Leaves impressed-veined. 



Calyx-lobes usually deeply cut ; nutlets deeply pitted on the ventral faces. 



III. Macracanthae. 

 Calyx-lobes less deeply cut ; nutlets with shallow pits on the ventral faces, 



IV. Brainerdianae. 

 Leaves not impressed-veined. 



Petioles usuafly glandless. 



Calyx-lobes glandular-margined ; fruit more than 4" thick ; leaves not trilobate. 



V. Rotundifoliae. 

 Calyx-lobes not glandular-margined ; fruit 2"-^" thick ; leaves often trilobate 

 towards the apex. VI. Virides. 



Petioles always glandular. 



Petioles with small stalked glands. VII. Intricatae. 



Petioles with large, sessile glands. VIII. Flavae. 



tt Leaves broadest at the base. 



Leaves }i'-2'/2' long and wide, membranaceous ; calyx-lobes usually entire. 



Leaves yellow-green, often slightly pubescent ; fruit soft at maturity. IX. Tenuifoliae. 

 Leaves blue-green, glabrous (except aspera) ; fruit hard at maturity. X. Pruinosae. 

 Leaves i'-4' long and wide ; calyx-lobes usually serrate. XL Coccineae. 



2. Leaves deeply cut (only those of the vegetative shoots in C. spathulata). 



Leaf-lobes sometimes 15 ; thorns i"-g" long. XII. Oxyacanthae. 



Leaf-lobes 3-7 ; thorns I'-i 34'. XIIL Microcarpae. 



** Petioles about i" long. XIV. Parvifoliae. 



b. Leaves pubescent above, glabrous beneath; thorns Vi'-i' long; fruit black. 



XV. DOUGLASIANAE. 



B. Leaves conspicuously deltoid-cordate, glabrous. XVI. Cordatae. 



Group I. Crus-galli. 

 Leaves coriaceous, glandless; petioles Vi'-Y^' long; corymbs many-flowered; calyx-lobes lanceo- 

 late-acuminate, usually entire ; fruit red ; calyx-tube flattened ; flesh hard thin, greenish. 

 Leaves enti,re. 



Leaves 44'-4' long- . . , • ■ '• C. Crus-galli. 



Leaves J4'-2J4' long. ' 2. C.berberifolia. 



Leaves somewhat lobed. 



Styles and nutlets usually 2. 3. C. schizophylla. 



Styles and nutlets usually 3-5. 



Lobes of the leaves irregular, obtuse. 

 Fruit globose. 



Vegetative leaves oblong. ■ 4. C. denaria. 



Vegetative leaves round. 5. C. Reverchoni. 



Fruit ellipsoidal. 6. C. Canbyi. 



Lobes of the leaves regular, acute ; calyx-lobes serrate. 7. C. fecunda. 



Group II. Punctatae. 

 Leaves subcoriaceous ; petioles Y^'-Yi' long; corymbs many-flowered ; calyx-lobes lanceolate- 

 acuminate, usually entire ; flesh of fruit hard, thick ; calyx-tube usually flattened. 



* Written by Mr. W. W. Eggleston. 



