500 



TREES OF NORTH AMERICA 



acid; nutlets 3-5, usually 4, thin, narrow and acute at the ends, slightly ridged on the back 

 with a wide or narrow ridge, f ' long. 



A tree, 10-20 high, with a trunk 6'-8' in diameter and often 4-5 long, covered with 

 close dark gray bark separating into long narrow thin plate-like scales, stout spreading 

 branches forming a handsome open head, and slender nearly straight branchlets thickly 

 coated when they first appear with matted pale hairs, light brown and lustrous at the end 



Fig. 456 



of their first season, and dark gray-brown the following year, and unarmed or armed with 

 stout nearly straight or curved spines l'-2|' long. 



Distribution. Open woods and pastures in rich moist soil; northeastern Illinois (Mo- 

 kena, Will County, Glenellyn, Dupage County, Barrington, Glendon Park, Cook County, 

 Highland Park, Lake Zurich, Lake County) ; Fox Point, Milwaukee County, Wisconsin. 



X. DILATAT^E. 

 CONSPECTUS OF THE ARBORESCENT SPECIES. 



Flowers in broad 6-12-flowered corymbs. 



Leaves broad-ovate; fruit bright scarlet. 105. C. dilatata (A). 



Leaves nearly orbicular to oval; fruit dull red blotched with green, or orange-red. 



106. C. suborbiculata (A). 



Leaves ovate to slightly obovate; fruit crimson, pruinpse. 107. C. hudsonica (A). 



Flowers in very compact 5-7-flowered corymbs; leaves broad-ovate; fruit usually broader 

 than high, much flattened at the ends, dark crimson, very lustrous. 



108. C. coccinioides (A). 



105. Crataegus dilatata Sarg. 



Leaves broad-ovate, acute, truncate, cordate or slightly rounded at the broad base, 

 coarsely and generally doubly and irregularly serrate above with straight teeth tipped 

 with large dark glands, unequally lobed usually with 2 or 3 pairs of acute or acuminate 

 lateral lobes, about one third grown when the flowers open at the end of May, and then 

 light yellow-green, conspicuously plicate, roughened on the upper surface with short stiff 

 white hairs and glabrous on the lower surface, and at maturity smooth and glabrous, dark 

 green above, pale bekrw, 2'-2|' long, and almost as wide as long, with a slender midrib 

 and 4 or 5 pairs of thin primary veins; petioles slender, somewhat glandular, at first villose, 

 soon glabrous, often dark red toward the base after midsummer, l'-2' in length; leaves at 



