(61) 



2. Aplopappus. Involucre imbricate. Pap- 

 pus 1-seriate. Bristles rigid. 



3. Chrysopsis. Involucre imbricate. Pap- 

 pus 2-seriate, internal capillary, external 

 scaly. 



4. Lessingia. Kay-flowers enlarged, bnt 

 not ligulate. 



5. Baccharis. Dioecious. Shrub. 



bbb. Parts of pappus definite in num- 

 ber. 



1. Pentachasta. Pappus of 5-scabrous 

 bristles, shorter than the corolla, some, 

 times depauperate. 



2. Grindelia. Pappus aristate. 



cc. Branches of style not flat, but tap- 

 ering, sometimes with an appendix. 



aaa. Scales of the involucre herbaceous. 



1. Chaenactis. Pappus paleaceous. 



2. Senecio. Pappus capillary. 



bbb. Scales of the involucre scarious. 



1. Artemisia. Eeceptacle slightly convex. 

 Pappus 0. Akenes obovate with small 

 epigynous disc. 



2. Tanacetum. Eeceptacle slightly convex. 

 Pappus 0. Akenes costate with large 

 epigynous disc. 



