PERUVIAN REGIONS. 



U9 



Homaliaceae, 



Samydaceae, 



(Chrysobalanea;), 



Rhizophoraceaj, 



Coiiibretaceae, 



Melastomaceae, 



Myrtaceae, 



TurneraceiB, 



Dioscoreaceae, 



epidendric Oicliidaceae, 



Siiiilaceae, 



Hypoxidacese, 



Araceae, 



Melaiithaceae, 



Restiacese, 



Monotropeae, 



Orobanchacese, 



Proteaceae, 



the tribe Coryleae, 



the tiibe Betulineas, 



Coniferae proper, and 



HaemodoraceEe. 



The Second list is of tribes absent from Lower Peru; but making 

 their appearance high up on the Andes. 



Capparldaceae, 



Linaceaj, 



Rosaceas, 



Paronychiaceae, 



Crassulaceae, 



Curcurbitaceas, 



Lubeliaceas, 



Gentianacea;, 



Phytolaccaceae, 



Saatalaceae, 



Urticaceae, 



Ephedreae, 



IridacejE, 



Juncacese, (and 



the genus Lycopodium ) 



The infiltrated lowland. In rainless countries, the fact becomes 

 obvious, that soil, earthy or sandj', soaks up moisture by capillary or 

 molecular attraction ; and very generally, to the height of six feet or 

 more above the water-level. The vegetable growth sustained by the 

 infiltration of river-water, extends therefore beyond the marshy 

 ground, over the basal portion of the adjoining upland. 



The coolness of the air and water in Lower Peru, may account in 

 part for the numerous Chilian analogies : for the presence in the 

 infiltrated ground, of a "chilquilla" or willow-leaved Baccliaris ; a 

 tall species of Equlsetum ; one or more Gnaplialiams ; a Calceolaria ; 

 and an abundant willow, Salix Hamholdtlana, the only kind of tree 

 seen indigenous in Peru. 



Natural marshes proved rare ; beyond at least the extensive one 

 at the mouth of the Rimac. The river maintains the character of a 

 mountain-torrent to the end of its long course; the water clear and 

 flowing rapidly, but insufficient in quantity to force an open passage 

 to the sea; especially, as the large component pebbles of the sea- 

 beach allow free percolation. The slight obstruction along the base 

 of the heap gives rise to a small pool of back-water, surrounded by 

 drowned land; the tract being further kept up and enlarged by leakage 

 from the artificial canals of irrigation on the rising ground. 



Around the margin of the pool, as the water became shallow, an 

 extensive bed of Scirpus lacustrtH? commenced; the close-set stems 



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