Franseria. COMPOSITE. 345 



1. Fertile involucre l 2-celled, "armed with several stout or flattened and straight 



or merely curved spines. 



* Annual : spines on the fruit very flat and broad. 



1. F. Hookeriana, Xutt. A foot or so high, rough-hirsute : leaves twice 

 pinnatiticl, either green or strigosely hoary beneath : racemes panicled : fruiting 

 involucre smooth or sometimes sparingly hirsute, about 3 lines long ; its widely 

 spreading spines lanceolate- subulate and thin. Ambrosia acanthicarpa, Hook. 



Los Angeles, Brewer. Eastern borders of the State, Mono Lake, Bolandcr. Thence common 

 to Oregon, Texas, Nebraska, &c. Involucre apparently always one-flowered and one-celled. 



* % Perennial, sometimes woody at base. 

 +- Leaves twice or thrice pinnately parted, their ultimate divisions small. 



2. F. dumosa, Gray. Shrubby and divergently much branched, a foot or so 

 high, canescent with line and close white pubescence : leaves with rather few obtuse 

 lobes, some of them only simply pinnatifid : fruiting involucre nearly glabrous ; the 

 spines flat and subulate. Rep. Frem. 2nd Exp. 316. F. albicaulis, Torr. PI. 

 Fremont. 16. 



Gravelly plains, southeastern borders of the State, Coulter, Schott, Cooper, &c. Also in Arizona. 



3. F. pumila, Xutt. Herbaceous, a span high, canescently silky-hirsute : " root 

 creeping": leaves thrice pinnatind, the lobes crowded : spike dense : "spines of the 

 fruit not exserted." X 1 utt. in Trans. Am. Phil. Soc. n. ser. vii. 344. 



Near San Diego, Nuttall, Parry. All the specimens seen are young, and the fruit unformed. 

 But Delpino (Studj sopra Artem.), who makes of this a genus (Hernia mbrosia), says that the 

 upper fertile involucres are 2-celled and 2-flowered, the lower one-celled and one-flowered. Nut- 

 tall assigns short spines to the fruit. Very probably this species is a dwarf Ambrosia tenuifolia. 



4. F. bipinnatifida, Xutt. Herbaceous : stems decumbent or trailing, 2 or 3 

 feet long, somewhat hirsute : leaves twice or thrice pinnatind, canescently hirsute or 

 almost silky : spike dense : fruiting involucre nearly glabrous ; its spines rather 

 short, stout, conical-subulate, flattened. 



Along the sea-shore from San Diego to British Columbia. Fruiting involucre 4 or 5 lines 

 long, rather narrow. Perhaps, as Lessing supposed, a form of the next. 



-t- -t- Leaves undivided or merely incised. 



5. F. Chamissonis, Less. Herbaceous : stems trailing, a foot or two long, 

 stout, appressed-hirsute : leaves silky-canescent or silvery, varying from oval to 

 cuneate-oblong, contracted at base into a long petiole, unequally and obtusely ser- 

 rate, sometimes incised, rarely almost pinnatifid : spike dense : fruiting involucre 

 sparsely hirsute ; its spines very stout and flattish. F. Chamissonis, var. malvae- 

 folia, Less. F. cuneifolia, Xutt. 1. c. 



Sea-shore, in sand, from San Francisco north to British Columbia. 



6. F. deltoidea, Torr. Herbaceous with more or less woody base, low, canes- 

 cent with a tine and close woolliness, which is partly deciduous with age : branches 

 slender : leaves varying from deltoid-ovate or almost hastate to rhombic-lanceolate, 

 obtusely and finely serrate, sometimes sparingly incised, on slender petioles : sterile 

 heads rather loosely racemed : spines of the ovoid 2-flowered involucre flat and 

 thin, broadly lanceolate subulate, pubescent or almost glabrous. PI. Fremont. 

 15, & Bot. Mex. Bound. 86. 



Southeastern frontiers of the State : common on the Gila : also in Lower California if, as is 

 probable, this is also F. chenopodii folia, Benth. Bot. Sulph. 26, the older name. 



7. F. eriocentra, Gray. Shrubby, low, hoary-pubescent : branches slender : 

 leaves varying from cuneate to lanceolate, sparingly incised : heads mostly glomerate : 

 fruiting involucre and its rigid nearly terete subulate spines clothed with long vil- 

 lous wool. Proc. Am. Acad. vii. 355. 



