1570 CONTRIBUTIONS FEOM THE NATIONAL. HERBARIUM 



Shrub; stem glabrous; petioles 5 to 13 mm. long, villous; blades lance-ovate, 

 2 to 10 cm. long, 0.5 to 5 cm. wide, acuminate, rounded or acutish at base, ser- 

 rate, scabrous above, sparsely strigillose beneath; peduncles solitary, mono- 

 cephalous, shorter than the upper leaves; heads 15 mm. high; involucre cam- 

 panulate, 1 to 1.5 cm. wide, the phyllaries about 2-seriate, few, ovate, submem- 

 branaceous; achenes margined; squamellae well developed. (Description 

 compiled.) 

 Zexmenia serrata Llave in Llave & Lex. Nov. Veg. Descr. 1: 13. 1824. 



Known only from the type locality, San Jose del Corral, Mexico. 



Sarmentose shrub 4 meters high; branches pubescent; leaves opposite, petioled, 

 sublanceolate, serrate, rough on both sides, the younger pubescent beneath; 

 heads in umbelliform cymes; involucre 2-seriate, the phyllaries few, ovate, 

 recurved at apex; rays 10 to 12. (Description compiled.) 



73. OTOPAPPUS Benth. (in Benth. & Hook. Gen. PI. 2: 380. 1873, hyponym) 

 in Hook. Icon. PI. 12: 47. pi. 1153. 1873. 



RiiWERENCE: Blake, Journ. Bot. Brit. & For. 53: 229-235. 1915. 



Shrubs; leaves opposite; heads radiate or discoid, yellow; involucre 3 to 6-seri- 

 ate, graduate, the phyllaries indurate, often herbaceous-tipped; rays when present 

 fertile; achenes compressed, 2-winged, the wings decurrent on the awns, the inner 

 much larger; pappus of 2 awns and a lacerate corona of connate squamellae. 



Heads radiate. 



Leaves strigillose but smooth to the touch above, the hairs not tuberculate- 

 based. 

 Pedicels 1 to 3 cm. long 1. O. verbesinoides. 



Pedicels 2 to 7 mm. long. 



Outer phyllaries with conspicuous, spreading or reflexed, spatulate, herba- 

 ceous tips 2. O; trinervis. 



Outer phyllaries without conspicuous spatulate herbaceous tips. 



4. O. microcephalus. 

 Leaves rough above with tuberculate-based hairs. 



Branches and pedicels densely spreading-hispidulous 6. O. pringlei. 



Branches and pedicels strigillose. 

 Rays 1 cm. long; outer phyllaries with spreading or reflexed, spatulate, 



herbaceous tips 5 to 13 mm. long 5. O. scaber. 



Rays 2 to 6 mm. long; outer ph\dlaries without conspicuous spatulate 

 herbaceous tips. 



Heads 1.2 to 1.5 cm. wide 3. O. salazari. 



Heads 6.5 to 8 mm. wide 4. O. microcephalus. 



Heads discoid. 



Leaves 3 to 5.5 cm. long; branches hispic^ulous 7. O. xanthocarphus. 



Leaves 6.5 to 13.5 cm. long; branches loosely pilose 8. O. robustus. 



1. Otopappus verbesinoides Benth. in Hook. Icon. PI. 12: 47. j)l. 1153. 1873. 

 Perymenium sartori Schultz Bip.; Klatt, Leopoldina 23: 144. 1887, as 



synonym. 



Veracruz and Chiapas. Guatemala to Costa Rica; type from Chontales, 

 Nicaragua. 



Scandent or straggling shrub; stem strigillose; leaf blades ovate to lance-ovate 

 or oblong-elliptic, 7 to 18 cm. long, 1.8 to 4.5 cm. wide, repand-dentate to ser- 

 rulate, acuminate; heads 1.5 to 2.3 cm. wide, in cymose panicles of 3 to 5 at tips 

 of stem and branches, or solitary in the upper axils; outer phyllaries with reflexed, 

 linear to spatulate, herbaceous tips. 



2. Otopappus trinervis Blake, Journ. Bot. Brit. & For. 53: 231. 1915. 

 Known only from the type locality, Finca Irlanda, Chiapas. 



