196 University of California Publications in Botany [Vol. lo 



SYSTEMATIC TREATMENT 

 Explanation of Certain Terms Used in the Text 



Calyx tube should be interpreted to include the short hypanthium at the 

 base of the flower. Length of flower refers to the distance between the tip of the 

 wings and the apex of the pedicel. The terms Lower Sonoran, Upper Sonoran, 

 and Transition refer to life zones in which the different species herein treated 

 are found growing. In general, the Lower Sonoran extends from sea level to 

 the foothills, the Upper Sonoran comprises the Foothill Belt, and the Transition 

 covers the Yellow Pine Belt. Quotations followed by " Jepson '06, Kew Herb." 

 signify that these quotations Avere taken from a manuscript volume of notes 

 made by Dr. Jepson in 1906 while studying the types of Lotus and Hosackia 

 at the Kew Herbarium. 



LOTUS [Tourn.] L. 



Annuals or perennials, the perennials herbaceous or suffrutescent. 

 Leaves pinnately compound, rarely subpalmate ; leaflets one to many, 

 entire-margined ; stipules f oliaeeous, membranous, scarious, or gland- 

 like. Flowers in axillary umbels or rarely solitary, mostly leafy- 

 bracteate. Calyx cylindrical, with teeth more or less subequal. 

 Corolla whitish to j^ellow, tinged or streaked with red, rose, or purple ; 

 wings obovate or oblong, adhering at base to the gibbous keel by 

 means of a lobe or process; keel incurved, beaked, or obtuse. Petals 

 and diadelphous stamens attached to a short perigynous disk or 

 hypanthium. Ovary one to many-ovuled ; style incurved. Legumes 

 straight to strongly arcuate. 



Subgenus 1. Hosackia. Perennials; leaves odd-pinnate with 

 foliaceous, membranous, or scarious stipules ; flowers usually more 

 than 1 cm. long, several to many in long-pedunculate umbels ; legumes 

 dehiscent, straight, abruptly short-beaked, several to many-seeded ; 

 fruit not reflexed. 



Legumes linear-oblong, 3 or more mm. wide; bracts usually distant from the 

 umbel and often pinnately compound; pedicels 1 mm. to 1 cm. long; claws 

 of petals exserted beyond calyx tube; blades of the keel and banner 

 shorter than their claws. 



Densely gray-woo-lly ; calyx teeth linear-subulate, 1.5 to 3 mm. long 



1. L. incanus. 



Villous to glabrous; calyx teeth less than 2 mm. long. 



Villous to glabrate, often glandular; leaflets oblong to oval (obovate), 

 those of the variety glaucous on the under side; calxy teeth tri- 

 angular or subulate; legumes 2 to 4 cm. long 2. L. stipularis. 



Mature herbage glabrous, young herbage densely covered with short 

 arched hairs; leaflets oval, rhombic, or obovate, under side glaucous, 

 with few short appressed hairs; calyx teeth short subulate-tri- 

 angular (or longer); legumes 3.5 to 7 cm. long 3. L. crassifolius. 



