Hemizonia. COMPOSITE. 363 



* * Receptacle flat, with a distinct chaff for each of the 8 or 10 disk-flowers, half en- 

 closing its sterile akene : heads small : rays 5 : akenes smooth and even, but dull. 



G. H. virgata, Gray. More or less glandular, but glabrous or slightly hirsute : 

 stem slender, a foot or two high, simple or virgately branched : cauline leaves 

 linear ; the lower laciniate or almost pinnatifid ; upper entire ; those of the branches 

 and of axillary fascicles very small (2 or 3 lines long), crowded, each tipped with 

 a truncate gland : heads numerous, virgately racemose : corollas glandular, the 5 

 ligules short and broad : scales of the involucre and the similar chaff of the recep- 

 tacle rather chartaceous, obovate or oblong, conspicuously beset over the back with 

 large and prominent tack-shaped stipitate glands : akenes obovate, 5-angled : pappus 

 none. Bot. Mex. Bound. 100. 



Foot-hills, &c., from Napa to Los Angeles. Heads narrow, 3 or 4 lines long ; the glands often 

 a full half line in length, resembling those of the section Calycadenia. The gland terminating 

 the smaller leaves is more or less cup- shaped in the dried specimens. Disk-akenes almost fertile. 

 The plant exhales a balsamic odor. 



* * * Receptacle convex or conical, many-flowered, chaffy throughout; the chaff distinct : 

 heads middle-sized : rays rather numerous, and usually in more than one series, 

 short, apparently pale yellow : akenes hardly if at all rugose, those of the disk 

 some of them more or less fertile (these with a depressed central terminal areola). 

 ( Olocarpha, DC., excl. sp.) 



7. H. macradenia, DC. Loosely branched, a foot or two high, stout, hirsute 

 and viscid-glandular : lower cauline and radical leaves laciniate-pinnatitid ; the others 

 narrowly linear ; uppermost and those of the axillary fascicles filiform-subulate, 

 tipped with a truncate gland : heads mostly glomerate at the end of the branches : 

 scales of the involucre and some of the chaff beset on the back with large long- 

 stipitate glands : rays roundish-cuneiform, 3-lobed : fertile akenes obovate, 5-augled, 

 short-beaked from the inner angle : receptacle strongly conical : pappus none. 



Dry open ground, from the Bay of San Francisco southward. One of the commoner "Tar- 

 weeds," exuding a heavy-scented viscid matter, which blackens the noses of horses. Notwith- 

 standing its frutescent aspect, the root is annual, or at most biennial. 



8. H. pungens, Torr. & Gray. Simple and at length much branched, a span 

 to nearly a yard high, hirsute or sparsely hispid : cauline leaves pinnatifid, or the 

 lower bipinnatifid with short spinulose-acuminate lobes ; those of the branchlets 

 and fascicles entire, small and crowded, lanceolate or linear-subulate, rigid, spinu- 

 lose-tipped, as are the scales of the leafy-bracted involucre and the narrow chaff of 

 the receptacle : rays scarcely exceeding the disk, narrow, 2 - 3-toothed : pappus 

 none : receptacle strongly convex. Hartmannia pungens, Hook. & Am. ; Hook. 

 Ic. PI. t. 334. 



Dry hillsides, from San Francisco southward to San Diego, where a very sparingly hirsute form 

 occurs. The root of this species also is annual. Akenes as in the preceding, but smaller. 



9. H. Fitchii, Gray. Paniculately branched, rigid, a span to a foot high, villous 

 or somewhat hirsute : radical leaves 1 - 2-pinnately parted into few linear or subu- 

 late divisions ; cauline leaves (or the upper ones) like those of the branches, sub- 

 ulate-linear (about an inch long), rigid and spinulose-tipped, very pungent, the 

 villous pubescence generally accompanied with small very long-stalked glands : 

 heads foliose-bracteate : scales of the involucre subulate : rays oblong, 2-toothed, 

 little exceeding the disk : chaff of the convex and hairy receptacle pointless, bearded 

 with long villous hairs : fertile akenes obovate, 3-angled, smooth, very gibbous ; 

 sterile disk-akenes with a pappus nearly equalling their corollas, composed of 8 to 

 12 narrowly linear and rigid chaffy scales, which are more or less united at base 

 and fringed or bearded at tip. Pacif. R. Rep. iv. 108. 



Valley of the Sacramento ; Clear Lake ; Long Valley, Plunias Co., &c., to Carson Valley, 

 Alpine Co. A well-marked species : some younger and less villous forms resemble H. pungens; 

 but the chaff is not pungent, always more or less villous- bearded, and the pappus is characteristic. 



