LXXIII. COMPOSIT.E (OLIVER AND HIERN). 257 



Subtribe vii. Buphthalme^. 



Involucre at length subglobose, hard 49. Geigeuia. 



Involucre wide ; scales broadly scarious-appendaged . . . 50. Ondetia. 

 Involucre hemispherical ; scales pauci-seriate, the outer ones 

 usually herbaceous. 

 Pappus coroniform, consisting of short unequal palese and 



a few longer aristae 51. Anisopappus. 



Pappus consisting of paleae as long as the ovary . , . 52. Odontospebmum. 



Tribe V. Kellantholdeae. Capitula heterogamoua, radiate or 

 rarely discoid, ray-florets $ fertile or nenter, disk-florets 5 fertile or 

 sterile'; or capitula homogamous discoid unisexual or with all the 

 florets $ . Involucral bracts various. Receptacle paleaceous or rarely 

 on the disk, under the sterile florets, naked. Corolla of the herma- 

 phrodite florets tubular, regular, 4-5-cleft. Anthers appendaged at 

 the apex, at the base entire obtuse or scarcely tailed. Style-branches 

 of the § florets truncate or appendaged. Achenes various, usually 

 compressed or angular ; pappus aristate or shortly paleaceous or want- 

 ing. — Leaves, at least the lower ones, usually opposite. Flowers usually 

 yellow. 

 Capitula unisexual. Anthers scarcely cohering. Leaves 



alternate or mostly so Subtribe i. AmbrostM 



Capitula bisexual. Anthers cohering. Leaves mostly 

 opposite. 

 Palese of the receptacle usually folded or convex. 

 Achenes of the disk angular subterete or laterally 



compressed Subtribe ii. Verhesinea. 



Paleae of the receptacle flat or nearly so. Achenes of 



the disk more or less dorsally compressed . . . Subtribe iii. Coreopsidecs. 

 Subtribe i. Ambbosibje. 

 Involucre of the male capitula gamophyllous. Female capi- 

 tula 1 -flowered 53. Ambbosia. 



Involucre of the male capitula with free bracts. Female 



capitula 2-flowered 54. Xanthium. 



Subtribe ii. VEBBESiNazE. 

 Inner involucral bracts (or outer paleae of the receptacle) 

 embracing the fertile ray-achenes. 

 Eay-florets in one row. (Outer) involucral bracts 5, narrow 55. Sigesbkckia. 

 Ray-florets in many rows. (Outer) involucral bracts 4, 



broad 56. Enhtdba. 



Inner involucral bracts flat. 

 Paleae of the receptacle very narrow, usually few ... 67. Eclipta. 

 Paleae of the receptacle broader, numerous. 



Leaves mostly alternate 58. Sclbbocabpus. 



Leaves opposite. 

 Pappus forming a small cup or annulus, with or with- 

 out 2-3 aristae. 

 Ray-florets fertile. 

 Ligule small. Aristae of the pappus 2 or 3, per- 

 sistent 69. Blainvillpa 



Ligule conspicuous. Aristae or short setae of the 



pappus caducous 60. Wedei.ia. 



Ray-florets neuter. Ligule conspicuous . . . . 61. Aspilia. 

 Pappus consisting of distinct aristae, rarely reduced 

 to teeth, not forming a cup or annulus. 

 VOL. III. K 



