148 GENTIANACEAE 



Family 98. OLEACEAE Lindl. 

 Woody plants with opposite leaves. Calyx 2-4-parted or none. Co- 

 rolla 2-4 parted or none. Stamens 2-4. Ovary superior, 2-celled, with 



two ovules in each cell. 



1. PRAXINUS L. 



Trees with odd pinnate leaves and polygamous or dioecious, racemose- 

 fasciculate flowers. Stamens two. Petals wanting. Fruit a flat- winged 

 1-2-seeded samara. 



Stalks of lateral leaflets Z"-V long. 1. F. Americana. 

 Stalks of lateral leaflets V'-2" long. 



Branchlets glabrous. 2. F. lanceolata. 



Branchlets-downy. 3. F. Pennsylvanica. 



1. P. Americana L. White Ash. A large tree : branchlets and peti- 

 oles glabrous : leaflets 7-9, stalked, ovate-orbicular to ovate-lanceolate, 

 sparingly denticulate or entire, pale and glabrate or slightly pubescent 

 beneath : wing of samara little decurrent. — Frequent throughout in the 

 upland woods. May. Very variable. 



2. P. lanceolata Borck. Gbeen Ash. 40°-60° high : wing of samara 

 noticeably decurrent : leaflets less pale below, glabrate or pubescent : 

 otherwise resembles the last. — In low grounds throughout, especially 

 along the Missouri River. May. 



3. P. Pennsylvanica Marsh. Red Ash. Differs from the last in 

 having the twigs, petioles and lower leaf surface velvety pubescent — Grow- 

 ing with the last around Hiffner's Lake near Atherton and Fish Lake 

 near Sibley. May. 



Family 99. GENTIANACEAE Dumort. 

 Glabrous herbs with opposite, entire, sessile, simple leaves without 

 stipules, and perfect, regular, oymose or clustered flowers. Divisions of 

 the calyx and corolla 4-12 each. Stamens as many as, and alternate 

 with, the corolla lobes. Ovary superior, 1-celled, with two parietal 

 placentae and many ovules. Capsule dehiscent by two valves. 



Style filiform ; anthers twisting in age. 



Corolla salver-form. 1. Eeytheaea. 



Corolla rotate. 2. Sabbatia. 



Style stout, short or none ; anthers not twisting. 3. Gentiana. 



1. ERVTHRAEA Neck. 

 Parts of the flower four to five. 



1. B. calycosa Buckl. Wkstken Centaury. 1° high : leaves linear- 

 oblong : flowers l'-2'' long, pinkish : corolla lobes obtuse. — Found as a 

 waif along the Santa Fe Railroad between the mouths of Rock and Sugar 

 Creeks. July. 



2. SABBATIA Adans. 



Flowers pinkish, handsome. 



1. S. campesttis Nutt. Pbaieie Pink. Annual, 4'-13' high : leaves 

 ovate to ovate-oblong : branches alternate : capsule 5-winged, its lobes 



