SONFLOWEE FAMILY. 547 



lower part of the crowded prickles and bearing at apex a pair of 

 strong beaks hooked or incurved at tip. 



Naturalized weed, native of the Eastern U. S., exceedingly abun- 

 dant in low lands, often covering hundreds or thousands of acres. 

 Flowering in summer and fruiting in autumn. 



2. X. spinosum L. Spi>'Y Ci-otbttr. Stems puberulent, much 

 branched; leaves lanceolate or ovate-lanceolate, acute or acuminate, 

 2 or 3-lobed or -cut, or the upper entire, narrowed at base into a short 

 petiole, green above, white-pubescent beneath, 2 to 5 in. long; by 

 the sides of the leaves are borne yellowish 3-pronged spines 1 in. 

 long; corolla pubescent with short rusty hairs; bur narrowly oblong, 

 J in. long, sparsely prickly; beaks inconspicuous, only one spinose. 



Naturalized European weed, a common summer tenant of barn- 

 yards and neglected fields: Sacramento, San Joaquin, and Coast 

 Range valleys and Sierra Foothills. 



Tribe 9. Inuieae. Everlasting Tribe. 



67. MICROPUS L. 



Small floccose-vfoolly annuals with entire leaves and scattered 

 several-flowered discoid heads. Bracts of the involucre open, scari- 

 ous, surrounding the flower-bearing bracts of the receptacle. Bracts 

 of the receptacle conduplicate, tipped with a scarious appendage and 

 almost concealed by the clothing of long loose wool, each one en- 

 closing a pistillate flower; sterile flowers In the center mostly naked. 

 Achenes gibbous, the corolla and style borne laterally, without 

 pappus, remaining enclosed in the cucullate bracts which finally fall 

 away from the receptacle. (Greek micros, small, and pous, foot, in 

 allusion to the soft- woolly heads. ) 



Beak-like tip to the Jruiting bract largely scarious, erect, short 



1. M. Califomicus. 

 Beak of the fruiting hract wholly hyaline, in anthesis as long as the body. 



2. M. amphibolus. 



1. M. Californicus F. & M. Slender, erect, 4 to 8 in. high, 

 commonly branched only at the very summit; leaves linear-oblong, 

 acuminate; receptacle low, with several scale-like processes; fruit- 

 bearing bracts 4 to 6, at length indurated, the surrounding bracts of 

 the involucre commonly 5; these orbicular or ovate, scarious, with a 

 green spot in the center; staminate flowers about 3, the corolla 

 filiform, but expanding somewhat toward the throat. 



Very common on low hills or valley land through the Coast 

 Ranges and Sacramento and San Joaquin Valleys to Southern 

 California. Last of Apr.-May. 



2. M. amphibolus Gray. Resembling the preceding but the 

 fruiting bracts 9 or 10 and comparatively thin and soft; receptacle 

 elevated or oblong; staminate flowers subtended by linear thin chaff'- 

 like bracts and with a pappus of few bristles. 



Walnut Creek, Brewer, no. 1015, 1862; too little known species. 



