CISTACEAE 797 



4. Helianthemum Georgianum Chapm. Steins erect or spreading, 1-3 dm. long, 

 usually branched at the base and above, often zigzag : leaf-blades oblong or slightly nar- 

 rower below the middle, 1-2 cm. long, flat or slightly revolute, paler beneath than above, 

 the lateral nerves as well as the midrib prominent beneath : flowers few, the petaliferous 

 with 12-16 stamens and 35 ovules, the apetalous with 8 stamens and 17 ovules : sepals 

 various, the larger ovate or oval, becoming 4 mm. long, acute or slightly acuminate: corolla 

 yellow, 15-18 mm. broad ; capsules ovoid-globose, about 4 mm. long, apiculate. 



In sandy soil, Georgia to Mississippi and Texas. 



5. Helianthemum Ndshii Britton. Stems several or numerous, ascending or decum- 

 bent, 1.5-4 dm. long, simple or sparingly branched above : leaf-blades oblong or linear- 

 oblong, 1.5-3 cm. long, acute or obtuse low down on the stem, the midrib and lateral 

 nerves rather prominent beneath : flowers in thyrsoid panicles, the petaliferous with 15 

 stamens and 8-10 ovules, the apetalous with 3 stamens and 3 ovules : sepals various, the inner 

 oval or oval-oblong, becoming 3-4 mm. long, obtuse : corolla yellow, 16-20 mm. broad : 

 petals broadly cuneate, slightly eroded : capsules broadly ovoid, 3-3.5 mm. long, blunt. 



In the scrub, peninsular Florida. 



6. Helianthemum thyrsoideum Barnhart. Similar to H. Nashii in habit, but the 

 leaves scarcely veined beneath, the inflorescence less widely branched, and the pedicels and 

 the sepals densely hirsute. 



In dry sandy soil, Hillsborough County, Florida. 



7. Helianthemum rosmarinifolium Pursh. Stems erect, 2-7 dm. tall, often branch- 

 ing throughout: leaf -blades linear or narrowly linear-oblanceolate, or those on basal shoots 

 broader, 1-2.5 cm. long, revolute, paler beneath than above, the midrib prominent beneath : 

 petaliferous flowers few, on filiform pedicels 1-1.5 cm. long, with 12-20 stamens and 8 ovules, 

 their sepals ovate, 2-2.5 mm. long, their corollas 12-15 mm. broad, their capsules 2-2.5 

 cm. long : apetalous flowers in dense clusters, with 3 stamens and 3 ovules, their capsules 

 short-pedicelled, about 1 mm. broad. 



In sandy soil, South Carolina and Arkansas to Florida, Mississippi and Texas. 



8. Helianthemum Canad6nse (L. ) Michx. Stem at first simple, later with slender 

 elongated branches, erect, ascending, or sometimes diflfuse, 1-6 dm. high : leaf-blades 

 oblong, linear-oblong or oblanceolate, nearly sessile, 1.2-3 cm. long, 4-8 mm. wide, rough 

 and dark green above, paler and canescent beneath, the margins commonly revolute in 

 drying : petaliferous flowers solitary, or rarely 2 together, with 30 stamens and 30-60 

 ovules, their sepals pilose, their corollas bright yellow, 1.8-3 cm. broad, their capsules 

 ovoid or obovoid, rounded above, 6-8 mm. long, much overtopped by the later elongating 

 axillary branches : apetalous flowers appearing later, axillary, nearly sessile, with 4 stamens 

 and 6-20 ovules, their capsules about 4 mm. in diameter : seeds papillose. 



In dry rocky or sandy soil, Maine to Indiana, Wisconsin, North Carolina and Kentucky. 



9. Helianthemum majus (L. ) B.S.P. Stem erect, 3-6 dm. [high, at first simple, 

 later with numerous short ascending branches : leaf-blades oblong-lanceolate or oblanceolate, 

 acute or obtuse, 1.5-3.5 cm. long, stellate-canescent beneath, darker above, short-petioled : 

 petaliferous flowers 5-12 in a terminal cymose raceme with 30 stamens and 30-60 ovules, 

 their sepals densely canescent, the outer nearly as long as the inner, their corollas 1.5- 

 2.5 cm. broad, light yellow, their capsules ovoid, 3-4 mm. long, little if at all overtopped 

 by the later axillary branches : apetalous flowers appearing later, witli 4 stamens and 6-20 

 ovules, minute, clustered in the axils, nearly sessile, their capsules about 2 mm. in diam- 

 eter : seeds evenly reticulated. 



In dry soil, Maine to Minnesota, South Dakota, Georgia and Texas. 



2. HUDSONIA L. 



Shrubs, with low tufted diffusely branched stems. Leaves small, subulate or scale- 

 like, imbricated. Flowers numerous, yellow, terminating branches. Petals 5, obovate- 

 oblong. Stamens 8. Style filiform. Stigma minute. Capsule 3-valved, included in the 

 calyx. Seeds few. Embryo slender, spirally curved. Beach Heathek. 



Flowers slender-pedicelled : leaves subulate : ovary pubescent. 



Ovary pubescent all over : one sepal, at least, with a linear-subulate lobe. 1. H. montana. 



Ovary pubescent at the top : one sepal, at least, with a tooth near the apex. 2. H. ericoides. 



Flowers sessile or nearly so : leaves scale-like : ovary glabrous. 3. H. tomeiitosa. 



1. Hudsonia montana Nutt. Bushy, somewhat villous throughout, the branches tufted 

 1-1.5 dm. long. Leaves commonly erect, sometimes spreading in age, filiform-subulate, 

 3-6 mm. long, approximate : pedicels 8-10 mm. long, slender, woolly-villous : flowers 



