32 BOTANY. 



tion, and seldom forming a dense sward, are exceedingly nutritious, and stock 

 will make long marches having no other food. Among them we may espe- 

 cially allude to the various " bunch-grasses" of Colorado, i, e., Eriocoma, 

 Festuca, and Poa, and more notably still the Boutelouas of Southern Arizona, 

 where, without much distinction, all are called "grama". 



I am here again indebted to the researches of Dr. Loew for the following 

 analyses of grasses. See Lieutenant Wheeler's Annual Report to the Chief 

 of Engineers, 1875, page 138. 



Festuca ovina, from an altitude of 10,000 feet, on the Jemez Mount- 

 ains, New Mexico : 



Water 12.3 



Ash 5.4 



Fibre 30.2 



Fat ..... 1.5 



Aqueous extract (of which 0.07 is sugar) 12.2 



Sugar, formed on digestion with dilute hydrochloric acid 10.8 



Extracted by potassa, and loss 27.6 



100.0 

 Boutelotja oligostachya, collected September 7 in the Abiquiu Mount- 

 ains, New Mexico, at an altitude of 7,500 feet: 



Water 12.0 



Ash ; 7.8 



Fibre 24.4 



Fat 2.4 



Aqueous extract (0.08 sugar) , 14.1 



Sugar, formed on digestion with dilute hydrochloric acid 22.2 



Extracted by dilute potassa, and loss 17.1 



100.0 

 Bouteloua hiesuta, collected near Las Vegas, New Mexico, November 

 16, at an altitude of 6,500 feet ; it was dead and dry, but without loss of 

 nutritive properties : 



Water 130 



Ash 6.5 



Fibre 19.1 



F at 21 



Aqueous extract (0.09 sugar) ] 3 g 



Sugar, formed on digestion with dilute hydrochloric acid 2G. 3 



Extracted by dilute potassa, and loss. .• 19. 2 



100.0 



