TO JUNCTION OF GRAND AND GREEN RIVERS. 79 



the Animas and the Pinos have forced their way to join the San Juan. It is, in fact, an 

 expansion of the valley of the Animas, has been mainly excavated by its current, and 

 is everywhere covered with beds of transported material washed down from the mount- 

 ains.* 



As we descended into the valley and thus opened it more to the north, we gained 

 sight of a chain of mountains in that direction, which our guide calls Sierra de los 

 Pinos. These are quite lofty, and consist, as 1 discovered from the drift brought down 

 from them, of quart/ites, silicious slates, limestone, and granite, with some trap, but 

 with a prevalence of metamorphic over erupted rocks. The Rio de los Pinos is a clear, 

 cold, trout-stream, full as large as the San .Juan at the Pagosa. The bottom-lands are 

 wooded with willows, cottomvood, alder, etc., and scattered trees of yellow pine, the 

 latter of which mark its course in the open sage-covered country through Avhich it 

 flows, and have naturally suggested the name which it bears. 



The interval between the Rio de los 1'inos and Rio Florido is underlaid by the 

 Middle Cretaceous shales; is gently. rolling in outline, its more level surfaces covered 

 with sage (Artriiiixid /I'/rlci/ldta.), its rounded hills with cedars or scrub-oak. Here 

 and there are meadows of good grass, with a strong growth of annual plants. On the 

 whole, however, the nuintrv is less picturesque and less productive than that lying 

 south and east of it. 



The Rio Florido, or River of Flowers, is so named from the flowery meadows which 

 line its banks; meadows which, so far as we could see, are no broader, greener, or 

 more flowery than those which border the other rivers of this region. It is, however, 

 a bright, handsome stream, similar in character to the Pinos, and about half as large. 

 It is probably not more than thirty or forty miles in length; rises in the foot-hills of the 

 Sierra, de los Pinos, aud joins the Animas some fifteen miles southwest from where we 

 crossed it. The bowlders which it has brought down from its sources are quite varied 

 in character, aud probably give a very fair representation of the geology of the 

 mountains which it drains. Of these many are composed of coarse red granite, much 

 like that of the Santa Fe Mountains, black and white porphyry, closely resembling 

 that which is so abundant at the gold-mines in the Placer Mountains ; blue limestone, 

 containing many of the characteristic Coal-Measure fossils so common at Santa Fe, such 

 as 1'nxlnr/nx xrniim-firH/utus, P. nodosus, Spirifer camcratus, Chonetes mesolnl>, etc.; with 

 these are masses of red and white sandstone, probably Triassic. 



The course of the Florido lies altogether within the basin-like area of which I 

 have before spoken. The extent and character of this area were fully learned in an 

 excursion which I made from our camp on the Florido, about forty miles down the 

 Animas, to visit some extensive 1 and interesting ruins situated in the valley of that 

 stream some twenty miles above its mouth. From my notes of this trip I make the 

 following extracts : 



"Aiif/Hxf I/A. Left camp early with Pfeiffer, the Indian agent, Messrs. Fisher and 

 Dorsey, and several Indians, to visit the ruins reported to exist at a certain point on the 

 banks of the Animas ; crossed over in a direct line to the Animas, a distance of about 

 ten miles. All this interval is occupied by a gravel mesa, of which the surface is 



* Since named Animas Park. 



