1904] MAC DOUGAL—DELTA AND DESERT VEGETATION 53 
The character of the portion of the Colorado desert lying within 
the state of California is the subject of a recent paper by S. B. Parish,?° 
and need not be discussed further here. He says, concerning the 
delta: “the region bordering the Colorado River is too little known 
to permit exact statements regarding it.” 
The arid region of Baja California to the eastward of the main 
divide covers an area of much greater topographical diversity, but 
Fic. 5.—View to southeastward from Lerdo, Sonora; the gravel mesa bears scat- 
tering bushes of Covillea and Ephedra. 
With less rainfall probably than the Sonoran slopes across the Gulf, 
from which its flora is widely different in general composition. My 
examination of this part of the country was made from San Felipe 
Bay, which lies about 60%" south of the mouth of the Rio Colorado 
in latitude 31° N. The western shore of the Gulf between this 
point and the river is made up of a continuation of the mud-flats of 
the delta, and has great expanses covered with Cressa and salt grass. 
© ParisH, S. B., A sketch of the flora of Southern California. Bor. Gaz. 36:203- 
222, 259-279. 1903. 
