DIVISION EIGHT — SCIENCE. 645 



BIDENS Linn. 



B. CHRVSANTHEMOIDES Miclix. O. K.; A. S. 



B. PiLOSA Linn. Along streets. July — October. 

 MADIA Molina. Tar-weed. 



M. DissiTiFLORA (Nutt) T. & G. Along street. July — September. 



M. SATiVA Mol. Frequent below 1,800 feet. June — August. 

 HEMIZONIA DC. Tar-weed. 



H. FASCicuLATA (DC.) T. & G. var. ramossima Gr. Com. Below 1,800 feet. 

 May— ^July. 



H. PUNGENS Torr. «& Gray. Frequent below 1,800 feet. May — August. 



H. TENELivA Gray. O. K.; A. S. April— June. 

 LAYIA Hook. & Arn. 



L. Gi^ANDULOSA (Hook.) H. & A. O. K.; A. S. April — ^June. 



L Pi^ATYGLOSSA (F. & M.) Graj'. (Tidy-tips) Com. below 2,000 feet. April — ^June. 

 ACHYRACHAENA Schauer 



A. MOLLIS Schauer. Near Oak Knoll. March — May. 

 BAERIA Fisch. & Mey. 



B. GRACILIS (DC.) Gr, Com. below 2,000 feet. March — May. 

 ERIOPHYLLUM Lag. 



E. CONFERTIFLORUM (DC.) Gr. Com. in unbroken soil below 3,000 feet. April — 

 June. 

 CH^NACTIS DC. "Pin-cushion." 



C. ARTEMisiAEFOLiA Gray. Frequent in dry unbroken soil below 3,000 feet. 

 June — July. 



C. GLABRIUSCULA DC. Frequent on dry hills. May — ^June. 



C. LANOSA DC. Com. below 3,000 feet. April — ^June. 

 HELENIUM Linn. Sneeze-weed. 



H. PUBERULUM DC. O. K.; A. 8., canyons of S. G. Mts. June — October. 

 ACHILLEA Linn. Yarrow. 



A. MILLEFOLIUM Linn. Com. in foothills of S. G. Mts. and adjacent plains. May 

 August. , 



ANTHEMIS Linn. Chamomile. 



A. COTULA Linn. Com. below 1,500 feet. April — July. 

 MATRICARIA Linn. 



M. DiscoiDEA DC. Com. below 1,500 feet. February — April. 

 ARTEMISIA Linn. Worm-wood. "Sage-brush." 



A. CALiFORNiCA Less. (California "Sage-brush.") Com. in dry unbroken soil 

 below 4,000 feet. May — August. 



A. DRACUNCULOiDES Pursh. Frequent below 2,000 feet. May — August. 



A. LUDOViciANA Nutt. Occasional below 2,000 feet. June — August. 



A. VULGARIS Linn. var. californica Bess. Common below 2,500 feet. June — 

 August. 

 TETRADYMIA DC. 



T. COMOSA Gray. Near Devil's Gate. July — August. 

 LEPIDOSPARTUM Gr. 



L. soUAMATUM Gr. A. S., foothills S. G. Mts. July — September. 

 SENECIO Linn. Groundsel. 



S. CALiFORNicus DC. Com. below 3,000 feet. March — May. 



S. DOUGLASii DC. Hills along A. S., foothills S. G. Mts. July — September. 

 CARDUUS Tourn. Thistle. 



C. CALIFORNICUS (Gr.) Greene. O. K., R. C. May— July. 



C. occidenTalis Nutt. Frequent below 2,000 feet. April — ^June. 

 SILYBUM Gaerth. Milk-Thistle. 



S. marianum (Linn.) Gaerth. Near Oak Knoll. May — ^July. 

 CENTAUREA Linn. Star-Thistle. 



C. melitensis Linn. Com. below 2,000 feet. May — August. 

 PEREZIA Lag. 



P. microcephala Gr. O. K., A. 8., foothills 8. G. Mts. June — August. 



MICROSERIS Don. 



M. linearifolia Gr. Com. below 3,500 feet. February — May. 



