Doyvtr—Rio del Fuerte of W. Mexico, and its Tributaries. 75 
smaller features; a great deal of work can be done by it without 
dismounting, especially as Mexican horses, being trained with 
severe bits to the use of the lasso, are very intelligent and steady. 
Observations for latitude were made with a 6 inch sextant and 
covered mercury trough. 
Heights were measured by boiling-point instrument with 
thermometers verified at Kew, and two aneroids. 
Sketches were drawn in outline at the point of view, and 
named from local information given by Indian or Mexican guides. 
OBSERVATIONS oF LATITUDE MADE BY THE AUTHOR. 
The town of Fuerte, 5 BS BY BO” Weedon, 
Agua Caliente de Baca, . 26° 13’ 40”  ,, 
Ranch of Septentrion, Ee Og Ogre Oi. ak, 
Santiago near Bahuina, . 27° 0% 30” = 
Town of Cuiteco, . 2 On he Oe 
Ojito de Barranca at the 
bend of the Urique river, 27° 13’ 40” ,, 
Bocoyna on the Rio Conchos, 27° 40’ 20”  ,, 
List oF SKETCHES AND Map. 
(Plates VI.-XV.) 
VI. La Puerta Blanca. 
VII. Grand Barranca of the Urique River. 
VIII. Cerro de Volcan. 
IX. Red barrier rock of Realito. 
X. River channel through lacustrine deposits. 
XI. Hroded edges of lacustrine sandstones. 
XII. Batopilas River from San José. 
XIII. Urique cafion, near Guapalaina. 
XIV. Panorama from El Ojito. 
XV. Map of Foothills of the Sierra, Western Mexico. 
NoTE ADDED IN THE PREss. 
The Author’s attention has been directed to the Bosquejo geolégico 
de México, 1897, numbers 4, 5, and 6, which contain a general account 
of the geology of Mexico, and some preliminary notes on the provinces 
of Chihuahua, Sonora, and Sinaloa. 
