112 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



In the present paper I have departed from the usual 

 method by describing a single type plant and indicating the 

 variations in the notes. Personal experience has proven 

 that the fuller a description is, the more value it has in the 

 determination of specimens; details seemingly of little im- 

 portance at the time when the specimen was described, are 

 often indispensable in the work of later students, making it 

 an absolute necessity for them to refer to the type specimen 

 in order to determine what was really described. This 

 brevity in some of the earlier descriptions makes them 

 entirely valueless for determination. 



Having no personal knowledge of the Mexican species 

 outside of the herbarium, I have not included them in this 

 revision, being unable to add anything of value. There is 

 a large and almost unknown field in Arizona and western 

 New Mexico which will probably yield several new species. 



Only the description and when possible the locality (the 

 original locality is quoted in nearly every instance) of the 

 species have been given in the following pages, the 

 synonymy having been omitted because of its often 

 doubtful nature. 



Key to the Species of Calochortus. 



Section I. Eucalochortus. 



Flowers or fruit nodding; petals incurved or strongly arched; gland trans- 

 versely crested or hairy; capsule nodding, with thin acute or winged cells; 

 leaves long and glossy, not channeled. 



Group I. Globe Tulips. 

 Type of Group C. albus. 

 Flowers subglobose, nodding. Woodland plants; California. 



Flowers white; petals covered with scattered silky hairs within. 



I. C. albus. 



Flowers rose color; petals silky within, partly opening out. Foot- 

 hills of Fresno and Tulare counties, California. . 2. C. amcetttis. 



Flowers light yellow; petals silky within, gland bordered with stiff 

 hairs which cross each other 3. C. pulchellus. 



Petals very strongly inarched, not silky within, but margin thickly 

 set with short, stiff hairs; gland like last 4. C. amabilis. 



