138 Expedition to the 



or in the mining district at the sources of the Gasconade, the 

 Meramt-g, and the St. Francis, will for a moment mistake it 

 for any of those varieties of transition or primitive limestone, 

 which it in some respects so closely resembles. The crystal- 

 line varieties, no less than the compact blue limestones, em- 

 brace numerous masses of chert or hornstone. This occurs 

 of various colours, and these are arranged in spots or stripes. 

 Some specimens have several distinct colours arranged in, 

 zigzag lines, somewhat resembling the fortification agate. 

 The hunters use fragments of this stone for gun flints; the 

 savages also formerly employed it in the manufacture of ar- 

 row points and other implements.* 



The soil superimposed upon these strata of limestone, is 

 a calcareous loam. Near the rivers it is intermixed with sand; 

 this is also the case with the soil of the high prairies about 

 the Konzas village. In ascending the Konzas river, one 

 hundred, or one hundred and twenty miles from the Mis- 

 souri, you discover numerous indications, both in the soil, 

 and its animal and vegetable productions of an approach to 

 the borders of that great Sandy Desert, which stretches east- 

 ward from the base of the Rocky Mountains. You meet 

 there with the orbicular lizard or " horned frog," an inha- 

 bitant of the arid plains of New Mexico. You distinguish 

 also some cacti, as well as many of those plants allied to 

 chenopodium, andsalsola, which delight in a thirsty muriati- 

 ferous soil. The catalogue of the forest trees belonging 

 to the vallies of this region is not very copious. The 

 cotton wood, and the plane tree, every where form conspi- 

 cuous features of the forests. With these are intermixed 

 the tall and graceful acacia, the honey locust, and the bonduc 

 or coffee tree,f and several species of juglans, carya and 



. * Jessun's MS. Report. 



f The Guilaudina *!ioiea of I. inn. Marshall, &c. hut referred by Micbaux 

 to the new genus Gymnocladas of which it is the only well ascertain- 



