1518 COXTB.IBUTIOlSrS FROM THE NATIONAL HERBARIUM 



1. Guardiola carinata Robinson, Bull. Torrey Club 26: 233. 1899. 

 Known only from the type locality, Acaponeta, Tepic. 



Suffrutescent, glabrous and glaucous; petioles about 1.2 cm. long; leaf blades 

 3 to 4 cm. long, 2 to 3 cm. wide, cordate-hastate, serrulate, obtusish; heads few 

 or solitary. 



2. Guardiola angustifolia (A. Gray) Robinson, Bull. Torrey Club 26: 235. 



1899. 

 Guardiola tulocarpus angustifolia A. Gray in S. Wats. Proc. Amer. Acad. 22: 



423. 1887, hyponym. 

 Jalisco; type from Tequila. 



Suffrutescent, about 60 cm. high, essentially glabrous; petioles 6 to 14 mm. 

 long; leaf blades 5 to 10 cm. long, 4 to 23 mm. wide, acuminate, sharply serrate 

 or serrulate; heads numerous in small cymose panicles. 



3. Guardiola stenodonta Blake, Proc. Biol. Soc. Washington 37: 56. 1924. 

 Known only from the type locality, Balboa, Sinaloa. 



Suffrutescent, practically glabrous; leaves slender-petioled, the blades 5 to 8 

 cm. long, 1.5 to 2.2 cm. wide at base across the very narrow spreading lobes, 

 abruptly contracted above them and then widened to middle, serrate; heads in 

 small terminal clusters. 



40. MELAMPODIUM L. Sp. PI. 921. 1753. 



Referexce: Robinson, Synopsis of the genus Melampodium, Proc. Amer. 

 Acad. 36: 455-466. 1901. 



Herbs, or sometimes suffrutescent; leaves opposite; heads radiate, the rays 

 fertile, yellow or white, the disk sterile; outer phyllaries usually 5, subherbaceous; 

 receptacle paleaceous; ray achenes tightly enveloped in the subtending indurate 

 phjdlaries, these often provided with a hood or horn at apex; pappus none. 



Rays W'hite; leaves not silky-pubescent. 



Stem and leaves densely cinereous-tomentose 1. M. argophyllum. 



Stem and leaves green or cinereous-pubescent, not tomentose. 

 Lamina of the rays 5 to 8 mm. long, not prominently venose. 



2. M. cinereum. 

 Lamina of the rays 1 to 1.3 cm. long, prominently venose. 



3. M. leucanthum. 

 Rays yellow; leaves silky-pubescent beneath, at least when young. 



Fruiting phyllaries with well-developed hood 4. M. nelsonii. 



Fruiting phyllaries with obsolete hood 5. M. heterophyllum. 



1. Melampodium argophyllum (A. Gray) Blake, Contr. U. S. Nat. Herb. 22: 



606. 1924. 

 Melampodium cineream argophyllum A. Gray; Robinson, Proc. Amer. Acad. 36: 



4.58. 1901. 

 Coahuila and Xuevo Leon; type from the Sierra Madre south of Saltillo, 

 Goahuila. 



Suffruticulose, about 20 cm. high; similar to M. cinereum except for its cinere- 

 ous-tomentose pubescence. 



2. Melampodium cinereum DC. Prodr. 5: 518. 1836. 



Coahuila; type from ''near San Fernando, Mexico." ^ Texas. 



Suffruticulose, several-stemmed, much branched, about 20 cm. high, cinereous- 

 pubescent; leaves linear to lance-oblong, 2.5 to 4 cm. long, entire to deeply 

 sinuate-lobed; fruiting phyllaries with muticous hood. 



1 According to Gray, Syn. Fl. 12; 239. 1884, the habitats and numbers of 

 specimens cited under M. cinereum and M. ramosissimum were interchanged in 

 De CandoUe's Prodromus. 



