ii2 Flora of the Palouse Region 



Family 42. CAEUTRICHACEAE. 



Aquatic or rarely terrestrial herbs: leaves opposite, entire, 

 spatulate or linear, without stipules: flowers minute, perfect or 

 monoecious, axillary: perianth none: bracts two, sac-like or none: 

 stamen 1: pistil 1; styles 2, filiform; ovary 4-celled; ovules 1 in 

 each cell: fruit compressed, lobed, more or less winged, or keeled; 

 endosperm fleshy. 



180. CAIXITRICHE. 



Low slender usually tufted herbs: leaves spatulate or linear or 

 both, entire: flowers monoecious or 2 or 3 in the axil of a leaf, 

 with or without bracts: staminate flowers a single stamen: pis- 

 tillate flower a single 4-celled ovary, sessile or pedicelled, with 2 

 distinct sessile stigmas: fruit nut-like, 4-lobed, 4-celled. 



C. palustris L. Aquatic or growing in the mud: floating leaves obovate, 

 obtuse or emarginate, the others linear or spatulate, i-nerved, 1-2 cm. long; 

 when terrestrial, leaves all linear: bracts 2, as long as or longer than the 

 fruit or wanting: fruit oval, emarginate, 1 mm. long, the edges grooved and 

 narrowly winged: styles erect, shorter than the fruit. Not rare, in ponds 

 and pools. 



Family 43. AXACARDIACEAE. 



Trees or shrubs with resinous or milky acrid juice: leaves alter- 

 nate, simple or compound, without stipules, not punctate: flowers 

 regular, small, polygamo-dioecious or perfect: calyx 3-7-lobed: 

 petals 3-7, rarely none; stamens as man}' or twice as many as the 

 petals, rarely fewer or more: styles 3; ovary 1 -celled; ovules one 

 in each cell: fruit generally a small drupe: endosperm scant or 

 none. 



181. RHUS. 



Trees or shrubs, some poisonous to the skin: flowers polygam- 

 ous or dioecious, seldom truly perfect, small, greenish or rarely 

 yellow or rose-color: calyx small, 5-parted: petals 5: stamens 5: 

 ovule basal. 



Leaflets 9-31: fruit red. R. glabra. 



Leaflets 3: fruit white. R. toxicodendron 



R. glabra L. .Shrub or small tree, 2-5 m. high, with ridged bark, glab- 

 rous and somewhat glaucous except the inflorescence: leaflets 9-31, broadly 

 lanceolate, acuminate, serrate, paler beneath, 5-8 cm. long: inflorescence a 

 dense panicle, usually puberulent, 10-12 cm. long: flowers green or yellow- 

 ish, polygamous: drupes red, 4-5 mm. in diameter, densely clustered, covered 

 with short hairs. Common along Snake River. 



