Explanations of Plates 24 to 35, Genus Chrysothamnus. 



Plate !24. 



Chrysothamnus paniculatus. (Drawn from fresh material 

 from east side of Tehachapi Pass, Calif.) 



(1) Portion of the inflorescence, X 1. 



(2) Habit sketch of an old plant, woody through- 



out, X 0.03. 



(3) Surface view of the middle portion of a leaf 



to show the resin-pits, X 20. 



(4) Head, X 3. 



(5) Outer bract of the involucre, X 9. 



(6) Inner bract, X 9. 



(7) Flower with part of pappus removed, X 6. 



(8) Style-branches, X 12. 



(9) Anthers, X 12. 



Chrysothamnus teretifolius. (Material from Inyo and 

 Kem Counties, Calif ., 32917 and 194530 UC.) 



(10) Branch showing leaves and inflorescences, X 1. 



(11) Branch with a narrow mflorescence, X 1. 



(12) Sketch of plant growing among rocks at 



Benton, California, X 0.05. 



(13) Head showing thickened tips to the bracts, X 3. 



(14) Outer bract of the mvolucre, X 9. 



(15) Inner bract, X 9. 



(16) Flower with part of pappus removed, X 6. 



(17) Style-branches, X 12. 



(18) Anthers, X 12. 



(19) Surface view of the middle portion of a leaf 



to show the resin-pits, X 20. (See fig. 24o, 

 p. 160, for cross-section.) 

 Plate 25. 



Chrysothamnus gramineus. (Drawn from the type 

 specimen.) 



(1) Upper portion of the stem showing the arrange- 



ment of the heads and the broad leaves, X 1. 



(2) Head showing the broad truncate bracts, X 3. 



(3) Outer bract of the mvolucre, X 9. 



(4) Inner bract, X 9. 



(5) Flower with part of pappus removed and 



showing elongated glabrous achene, X 6. 



(6) Style-branches showing the very short stig- 



matio portion and the long appendages, X 12 



(7) Anthers, X 12 



(8) Habit sketch showing part of plant, X 0.12. 

 Chrysothamnus vaseyi. (Material from Panguitch 



Lake, Utah, 159879 UC.) 



(9) Portion of plant showing the erect leafy shoots 



and the inflorescences, X 1. 

 (10) Head, X 3. The bracts are greenish and 



slightly thickened near the tip. 

 (U) Outer bract of the involucre, X 9. 



(12) Inner bract, X 9. 



(13) Flower with a portion of the pappus removed 



and showing the short glabrous achene, X 6. 



(14) Style-branches showing the elongated stigmatic 



portion and the short appendages, X 12. 



(15) Anthers, X 12. 

 Plate 26. 



Chrysothamnus viscidiflorus lanceolatus. (Material 

 from Cerro Sunmiit, Colorado, 55164 UC.) 



(1) Branch showing leaves and inflorescence; herb- 



age puberulent; X 1. 

 Chrysothamnus msddiflorus puberulus. (Material from 

 Northern Nevada, 175448 UC.) 



(2) Branch showing leaves and inflorescences; 



herbage puberulent; X 1. 



(3) Head, X 3. 



(4) Outer bract of the involucre, X 9. 



(5) Inner bract, X 9. 



(6) Flower with part of pappus removed, X 6. 



(7) Style, X 12. 



(8) Anthers, X 12. 



Plate 26 — continued. 

 Chrysothamnus viscidiflorus humilis. (Drawn from 

 material of the type collection, 87252 UC.) 

 (9) Portion of plant showing leaves and inflores- 

 cences; herbage puberulent; X 1. 

 Chrysothamnus visddifiorus elegans. (Material from 

 Gunnison Valley, Colorado, 193530 UC.) 



(10) Summit of branch with inflorescence; herbage 



puberulent; the leaves in this and other sub- 

 species may be either twisted, as here shown, 

 or straight, bracts greenish-tipped; X 1. 

 Chrysothamnus viscidiflorus stenophyllus. (Drawn from 

 specimen of type collection, Watson 566, NY.) 



(11) Summit of branch with inflorescence; herbage 



glabrous; X 1. 

 Chrysothamnus viscidiflorus pumilus. (Material from 

 Pocatello, Idaho, 193103 UC.) 



(12) Summit of branch, wath inflorescence; herbage 



glabrous; X 1. 

 Plate 27. 



Chrysothamnus viscidiflorus Unifolius. (Drawn from 

 fresh material from Point of Rocks, Wyo.) 



(1) Leafy stem and inflorescence; herbage glab- 



rous; X 1. 



(2) Head showing the slightly thickened greenish 



tips to the bracts of the involucre, X 3. 

 Chrysothamnus viscidiflsrus typicns. (Drawn from 

 material from Weber Caiion, Utah, preserved 

 in hquid.) 



(3) Inflorescence and leaves; glabrous; X 1. 



(4) Head, X 3. 



(5) Outer bract of the involucre, X 9. 



(6) Inner bract, X 9. 



(7) Flower with part of pappus removed, X 6. 



(8) Style-branches, X 12. 



(9) Habit-sketch of a plant at Buena Vista, 



Colorado; X 0.1. 

 Plate 28. 



Chrysothamnus greeneifilif alius. (Material from Lund, 

 Utah, 203159 UC.) 



(1) Leafy shoot with inflorescence, X 1. 



(2) Anthers, X 12. 



(3) Head, X 3. 



(4) Outer bract of the involucre, X 9. 



(5) Inner bract, X 9. 



(6) Flower with part of pappus removed, X 6. 



(7) Style-branches, X 12. 



Chrysothamnus albidus. (Drawn from fresh material 

 from the type locality.) 



(8) Leafy shoot with inflorescence, X 1. 



(9) Habit sketch of a plant growing on an alkaU 



flat; C. nauseosus consimilis and Elymua 

 condensatus in the background; X 0.05. 



(10) Surface view of middle part of leaf to show resin- 



pits, X 20. (See fig. 246, p. 160, for cross-section.) 



(11) Anthers, X 12. 



(12) Flower with a portion of the pappus removed; 



the curved corolla is characteristic; X 6. 



(13) Outer bract of the involucre, X 9. 



(14) Inner bract, X 9. 



(15) Style, X 12. 



(16) Head, X 3. 

 Plate 29. 



Chrysothamnus pulchellus typicus. (Material from 

 Chihuahua, 87217 UC.) 



(1) Branch, X 1. 



(2) Outer bract of the involucre, X 9. 



(3) Inner bract, X 9. 



(4) Habit sketch of a plant growing in northwestern 



New Mexico, X 0.1. 



