272 



MICRANTHI. 29. 



Flowers very small, mostly 3-8 mm. long (12-15 mm. 

 long in the Pringlei group, in Madrensis and ervoides), 

 in heads, or spikes, or rarely in short racemes, nearly 

 always reflexed. Calyx about campanulate, 1-3 mm. 

 long. Pedicels very short. Bracts small. Pods oblong 

 to linear, little arched but always oblique, small, 4-12 

 mm. long, 2-celled (imperfectly so in Purpusi), trique- 

 trous to reniform in cross section, not inflated or but little 

 so, papery to chartaceous, sessile or minutely stipitate 

 (stipitate in A. Purpusi), rounded to notched at base, 

 sharply acute (merely apiculate in Seatoni), sulcate dor- 

 sally, ventral suture raised and thickened. Woody 

 rooted perennials (possibly annual in A. Pringlei) with 

 slender stems, either short and csespitose or long and 

 widely spreading, rarely erect. The Mexican species of 

 this group are poorly known and arrangement and spe- 

 cies are only tentative. 



KEY. 



A. Flowers few and in racemes. 



AB. Pods much laterally flattened, with ventral suture the more 

 arched and tip conspicuously declined, nearly oval, 4-5 mm. 

 long. 



Pods Wdolly, covered by the leaveS. 243 lenliformis. 



A2B. Pods very broad or obcompressed in cross section, oblong 

 to linear, arcuate, about 1-1.5 cm. long. Flowers purple- 

 tipped, broad. Calyx campanulate. Peduncles slender, 5-10 

 cm. long. Leaflets elliptical, rounded or barely acute. Stems 

 slender from a woody root. Stipules small. 

 Pedicels evident. 



Foliage ashy. 244 Madrensis. 



Foliage nearly smooth. - 245 ervoides. 



Pedicels almost none. j' 



I\)ds 1-2 cm. long. 246 Grfeggii. 



Pods 7-10 mm. long. 247 Luisianus. 



2A. Flowers in heads. 



2A'B. Flowers and pcds reflexed in dense heads at the ends of 

 filiform peduncles. Calyx turbinate-campanulate, the tube 

 about 1 mm. long. Flowers 4-5 mm. long, broad. Pods 

 about 8 mm. long and 2 mm. high, laterally flattened, very 

 obtuse. 



Internodes elongated and stems almost tilifonn. 24^ Pue!)lae, 



2A2B. Flowers ascending, few, in loose heads. Calyx campanu- 

 late. Pods apiculate or very short-pointed, not reflexed. Flow- 

 ers narrow, 7-12 mm. long. Banner oblong-ovate. Wings 

 about 1 mm. wide. Calyx tube about 3 mm. long. Pubescence 

 ashy and minute. 



Pods oblong. 7-10 mm. long. 249 Pringlei. 



Pods linear, about i cm. long. 250 parvus. 



