4b 8 Expedition to the 



spinous processes of the back bone, and are from eighteen 

 to twenty-four inches in length. They are taken out with a 

 small portion of the flesh adhering to each side, and whether 

 roasted, boiled, or stewed, are certainly very far superior to 

 any part of the flesh of the domestic ox. 



29th. We had proceeded but a few miles from our camp 

 when it was found that Mr. Say's horse was so far exhaust- 

 ed as to be unable to proceed at the same pace as the other 

 horses. Mr. Say accordingly dismounted, and by driving 

 his horse before him, urged the animal along for a few miles; 

 but this being found too laborious, and as several of the hor- 

 ses were near failing, it was determined to halt, which we 

 did at 10 o'clock, and remained in camp during the day. 



The country, for several miles to the west of the range of 

 hills mentioned above, is as uniformly plain as that on any 

 part of the Platte. It differs from that further to the east 

 onlj in being of a coarser sand, and in an aspect of more 

 unvaried sterility. The cactus ferox reigns sole monarch, and 

 sole possessor, of thousands of acres of this dreary plain. It 

 forms patches which neither a horse nor any other animal 

 will attempt to pass over. The rabbit's foot plantation, and a 

 few brown and withered grasses, are sparingly scattered over 

 the intervening spaces. In depressed and moist situations, 

 where the soil is not so entirely unproductive, the variegated 

 spurge, (Euphorbia variegata^) with its painted involucrum, 

 and parti -coloured leaves is a conspicuous and beautiful or- 

 nament. The Lepidium virginicum, distributed over every 

 part of northern and equinoctial America, from Hudson's 

 Bay to the summit of the Silla of Caraccas,* is here of such 

 diminutive size that we were induced to search, though we 

 sought in vain, for some character to distinguish it as a se- 

 parate species. 



At three o'clock P. M. the planet Venus was distinctly 

 visible. Its distance from the sun at 3h. 45m. was east 36* 



•See Humb. Pers. Nar. Vol. 3. page 500, 



