360 
APPENDIX. 
vions on the Colorado; beginning to flower in January. Resembles tbe original specimens 
collected on tbe Gila by Major Emory. 
Siba heberacea, Torr. in Pl. Fendl. p. 23. River bottoms near Fort Yuma, and west to tbe 
Pacific ; August, September. 
Hibiscus BENUBATUS,-Re7^7*. Bot. Sulpli. p. 7, t. 3. California desert, January, May. 
Dalea Emoryi, Gray, PL Thurb. p. 315. Sandy soils on tbe Colorado and Gila. This and 
the following species, viz: D. spinosa, Gray; D. scoparia, Gray; D. frutescens, Gray; D. 
arborescens, Torr.; D. Fremontii, Torr.; and D. Schottii, n. sp., form a peculiar group, inter¬ 
mediate between Dalea and Psoralea, distinguished from tbe former by the truly papilionaceous 
corolla, and by all tbe petals being inserted at the base of the calyx; from tbe latter, (at 
least tbe North American species,) in habit, in tbe inonadelphous stamens, tbe upper part 
of the filaments being distinct, and in other characters. Other remarks on this group will bo 
made in the botany of tbe Mexican Boundary Survey. (Tab. II.) 
Dalea mollis, Benth. Pl. Eartw. p. 306. With tbe last; a smaller plant than tbe New 
Mexican variety. 
Cercibium floribum, Benth. Mss.; Gray, Pl. Wright, p. 58, ( adnot .) On tbe Colorado, and 
in the desert west. It is called Palo verde by the Mexicans, and Green Acacia by the Ameri¬ 
cans. It sometimes attains tbe height of 30 feet. (Tab. III.) 
Lupinus sparsiflorus, Benth. Pl. Eartw. p. 303. On the Colorado. Less hairy than the 
plant described by Bentham. 
Strombocarpa pubescens, Gray, Pl. Wright, 1, p. 60. Prosopis (Strombocarpa) pubescens, 
Benth. in Bond. Jour. Bot. 5 , p. 82. This is tbe well known Screw-bean of travellers in New 
Mexico and California. It occurs from tbe Rio Grande to the western slope of tbe Cordilleras 
of California. The pods are an important article of food to tbe Mexicans and Indians, and are 
also greedily eaten by cattle. (Tab. IY.) 
Opuntia tessellata, Engelm. Syn. Cact. p. 53, & in Cact. Whippl. Pad/. Railroad Surv. 
t. 21. Desert west of the Colorado. A remarkable species; well described and figured by 
Engelmann. 
Mammillaria phellosperma, Engel. Cact. Mex. Bound, p. 6, t. 7. Common on tbe Colorado. 
Mentzelia albicaulis, Torr. & Gray, FI. 1, p. 534. Sandy soils ; from the Gila to San 
Diego ; beginning to flower when scarcely an inch high. 
Mentzelia pumila, Nutt, in Torr. & Gray, FI. 1, c. On tbe Colorado ; beginning to flower 
in March. This agrees with Nuttall’s original specimens, and with others collected in Califor¬ 
nia by Fremont. 
CEnothera (chylismia) CLAVAiFORMis, Torr. & Frem,. in Frem. 2d Rep. p. 314. With the 
last. Anthers hairy. We fear that R. brevipes of tbe Botany of Whipple’s Expedition is a state 
of this species with considerably larger flowers and short pedicels. Intermediate specimens 
seem to connect them. We have a remarkable variety, collected by Fremont in 1849, (probably 
on tbe Lower Gila,) in which tbe lamina of the leaf is more than six inches long, deeply pin- 
natifid, the segments very unequal and coarsely toothed, the terminal one scarcely larger than 
some of tbe others. 
CEnothera (chylismia) carbiophylla (n. sp.): annua, caule folioso parce ramoso; foliis 
cordatis repando-dentatis, petiolo nudo ; capsulis elongato-cylindricis subsessilibus v. pedicello 
3_4-plo longioribus. Near Fort Yuma. Whole plant, when young, clothed with a soft white 
pubescence, most of which disappears with age. Stem 6-12 inches high. Leaves deeply cordate, 
