(108 ) 
49. Achillea L. Yarrow. 
Superflua. Head -flowerad; ray-flowers 5 
to 6, ligulate, ovate. Involucre ovate; scales 
imbricate, those of the receptacle hyaline. 
Akenes marginate; pappus 0. 2f. 
1. A. mr~LEeFoLIum L. Ray-flowers and disc 
pale.—Common. Summer. 
50. Matricaria L. CHamomite. 
Superflua. Aiqualis. Scales of the invo- 
lucre imbricate. Receptacle conical, naked. 
Akenes angulate. Pappus coroniform or 0. 
Disc yellow; flowers of the ray white.—© 
1. M. piscoira DC. Pappus 0; areola of 
akene merely surrounded by a rim; ray-flowers 
white, depauperate.—Summer. Common. 
2. M. occrpENTALIS Greene. Pappus coro- 
niform, unequal, the side toward the ray con- 
siderably developed, the inner side reduced to 
a rim.—Contra Costa. Summer. 
51. Chrysanthemum L. 
Superfiua. Involucre hemispherical, spread- 
ing. Scales o-seriate, imbricate, appressed. 
Receptacle not conical, naked. Akenes short, 
somewhat terete, costate, truncate at the apex; 
pappus 0. 
1. C.secerum L. Ray-flowers yellow.—©. 
Has been found near Oakland. Summer. 
