374 TREES OF NORTH AMERICA 



on slender pedicels, in drooping many-fruited clusters, short-oblong, dull dark crim- 

 son marked by large pale dots, about \' long and f'-^' wide; calyx only slightly 

 enlarged, the lobes reflexed and appressed; flesh thin, yellow, dry and mealy; nutlet 1, 

 gradually narrowed from the middle to the obtuse ends, grooved and irregularly 

 ridged on the dorsal face, or 2 and then broad, rounded at the ends, prominently 

 ridged on the back, with a high wide rounded ridge, about -fa long. 



A tree, sometimes 20 high, with a trunk 8' 12' in diameter, covered with smooth 

 light gray bark, spreading branches forming a round-topped head, and slender 

 slightly zigzag branchlets light orange-green when they first appear, becoming dark 

 purple and lustrous and ultimately grayish brown, and armed with many slender 

 straight or slightly curved dark purple-brown shining spines l'-2' long. 



Distribution. Neighborhood of Chicago to Joliet, Illinois, and on Belle Isle in 

 the Detroit River, Michigan. 



7. Crataegus algens, Beadl. 



Leaves obovate to oblong or elliptic, rounded or acute at the apex, gradually nar- 

 rowed and concave-cuneate at the entire base, sharply serrate above, villose on the 

 upper side of the midribs and nearly fully grown when the flowers open at the end 

 of May, and at maturity glabrous, subcoriaceous, dark green and lustrous above, 

 pale below, l^'-2' long, | '-1^' wide, with thin midribs and slender primary veins, 

 turning in the autumn to shades of orange, yellow, and brown; their petioles slender, 



wing-margined above, rarely glandular, with minute glands, about \' long. Flowers 

 ' in diameter, on slender elongated pedicels, in broad many-flowered glabrous corymbs ; 

 calyx-tube narrowly obconic, glabrous, the lobes slender, acuminate, entire or remotely 

 serrate; stamens 10; anthers yellow; styles 1-3. Fruit ripening in September and 

 October, on slender pedicels, in few-fruited hanging clusters, subglobose to obovoid, 

 $'-' in diameter, dull red, or green flushed with red, -f'-^' long; calyx somewhat 

 enlarged, with reflexed persistent lobes; flesh thin, yellow, dry and mealy; nutlets 

 usually 1 or 2, prominently ridged on the back, ^'-f ' long. 



A tree, 15-18 high, with a short trunk occasionally 7'-8' in diameter, stout 

 ascending wide-spreading branches forming a wide round-topped head, and branch- 

 lets armed with stout nearly straight spines l'-2' long. 



