136 



TREES OP THE NORTHERN UNITED STATES 



like, scaly, globular drupe, ripe in autumn. Bark scaling 

 off like that of the Sycamore. 



1. Pl&nera aqu&tica, Gmel. (AMERICAN 

 PLANER-TREE.) Leaves ovate-oblong, small, 1 

 to 1J^ in. long, on short stems, sharp-pointed, 

 serrate with equal teeth, smooth, green above 

 and gray below, not oblique at base. Flowers 

 minute, in small heads, appearing before the 

 leaves. Fruit a scaly, roughened nut, % in., 

 raised on a stalk in the calyx ; ripe in Sep- 

 tember. A small tree, 20 to 50 ft. high ; wet 

 banks, Kentucky and southward ; hardy as far 

 north as Philadelphia. 



2. Pl&nera acuminata. (KiAKA ELM 

 OR JAPAN PLANER-TREE.) Leaves large, 

 glossy, smooth, deeply notched, on red 

 strms ; young shoots also red. This is a 

 larger, more hardy, and finer tree than the 

 Amorican Planer-tree, and should be more 

 extensively cultivated. 



The Caucasian Planer-tree (Planera par- 

 vifolia), with very small leaves, is also oc- 

 casionally cultivated. 



GENUS 76. ClSLTIS. 



P. acuminata. 



Trees or shrubs with alternate, simple, 2-ranked, ob- 

 lique, serrate leaves. Flowers inconspicuous, greenish, 

 axillary. Fruit berry-like, sweet, edible drupes, about 

 the size of a currant, with one seed ; color dark ; ripe in 

 autumn. 



* Leaves usually sharply serrate 1- 



* Leaves almost entire 2. 



1. C61tis occidentalis, L. (SUGARBERRY. 

 HACKBERRY.) Leaves ovate, obliquely sub- 

 cordate to truncate at base, long-acuminate, 

 serrate (at least near the apex), rough above 

 and hairy beneath. Fruit a single-seeded, 

 % in., globular drupe, solitary on a peduncle, 

 1 in. long, in the axils of the leaves; purple when ripe in aiitumn. 



C. occidentalis. 



