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DAHLIA BARKERIiE. 



(Miss Barker's Dahlia.) 

 LINNEAN SYSTEM. Nq NATURAL ORDER. 



SYNGENESIA SUPERFLUA. COMPOSITE — ASTEROIDE^E. 



GENERIC CHARACTER. 



Dahlia (Cav.) Capitulum radiatum, floribus radii ligulatis foemineis neutrisve, disci 

 tubulosis 5-dentatis. Involucrum duplex, exterius squamis foliaceis 1-serialibus circiter 5 patulis 

 reflexisve, interius squamis 12-16 subbiserialibus longis apice membranaceis basi crassiusculis et 

 inter se coalitis. Receptaculum planum paleaceum, paleis membranaceis oblongis indivisis. 

 Styli rami erecti aut subincurvi crassi extus piliferi. Antherce ecaudatae appendicular. 

 Achcenium oblongo-obovatum obcompressum epapposum apice obsolete bicorne. — Herbas 

 Meocicance grandes. Folia opposita pinnati-partita rarius bipinnati-partita, segmentis ovatis 

 acutis serratis. Radices fasciculatss, aliis cylindricis, aliis oblongo-tuberculatis. Rami apice 

 elongati nudi 1-cephali. Capitula versicolora, disco nempe luteo, radio pm-pureo roseo albo aui 

 flavo. — {Be Cand. Prod. 5, p. 494.) 



Head radiated, flowers of the ray ligulate, female, or neuter, those of the disk tubular, 

 5-toothed. Involucre double, exterior one of about 5 leafy scales in a single series, spreading or 

 reflexed ; the interior one consisting of from 12 to 16 scales arranged somewhat in a double 

 series, long, membranaceous at the apex, a little thickened at the base, and united with each 

 .other. Receptacle flat, chaffy, scales membranaceous, oblong, undivided. Branches of the 

 style erect or somewhat incurved, thick, externally hairy. Anthers ecaudate, appendiculate. 

 Seed oblong-obovate, obcompressed, without pappus, obsoletely 2-horned at the apex. — Fine 

 Mexican plants. Leaves opposite, divided in a pinnate, more rarely in a bipinnate manner, 

 segments ovate, acute, serrated. Roots fasciculate, some cylindrical, others oblong-tuberculate. 

 Branches elongated at the apex, naked, 1-headed. Heads various in colour ; namely, with a 

 yellow disk, and purple, rose, white, or yellow rays. 



SPECIFIC CHARACTER. 



D. Barkerise ; caule solido scabrido hirsutissimo ramosissimo ; foliis hirsutis, foliolis ovatis 

 inciso-dentatis basi insequalibus ; floribus subconniventibus, pedunculis gracilibus superne glabris, 

 ligulis foemineis fertilibus, paleis fusco striatis. 



Stem solid, rather rough, exceedingly hairy, very much branched ; leaves hairy, leaflets 

 ovate, inciso-dentate, unequal at the base; flowers somewhat connivent, peduncles slender, 

 glabrous in the upper part, florets of the ray female, fertile, palece marked with brown strue. 



Dahlia Barkeriae, Flor. Cab. Vol. II. fol. 28. 



Descr. — Stem roughish, remarkably hairy, and very much branched from the base, forming 

 a compact bushy plant from 2 to 3 feet, in height, and from 5 to 8 in circumference. Leaves 

 consisting of from 2 to 3 pairs of ovate, inciso-dentate leaflets with a terminal one which is 



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