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On the mountains of the south of Europe, Poa disticha and other Grasses 

 ascend almost to the snow-line ; and, on the Andes, this is also the case with 

 Poa malulensis and dactyloides, Deyeuxia rigida and Festuca dasyantha. 



" The distribution is of greater importance. As to the chief groups 

 and species, their distribution will not attain a real interest until we shall 

 be in possession of a perfect natural classification ; for in this respect we are 

 still, in my opinion, far behind. The division of Beauvois appears to me too 

 artificial, and in that of Brown the groups Panicese and Poacese are too large. 

 The best, perhaps, is that of Kunth, according to which the Grasses are 

 arranged under ten groups. In respect of latitude, the relation of the Grasses, 

 in the system of Roemer and Schultes, in the hot and temperate zone, is the 

 following : — 



" Hence it follows that not one of these groups belongs exclusively to 

 either the one or the other zone, but that, on account of the proportionally 

 greater number, the Paniceee, Chlorideae, Saccharinse, Oryzeaj, Olyrea, and 

 Bambusaceee, may be regarded as tropical, and Agrostideoe, Bromese, and 

 Hordeacese, as extra-tropical forms ; and that there is, consequently, a con- 

 siderable contrast between the former of these two zones. On the contrary, 

 the difference between the various continents and degrees of longitude is in- 

 considerable. Neither in the torrid nor temperate zones has any group in the 

 continent a perceptible preponderance over another. The result also appears 

 to l)e the same, on comparing the two hemispheres : we know, however, too 

 little of the southern to state this precisely. In respect of elevation, the dis- 

 tribution, according to the degrees of latitude, is very similar; for, in the 

 mountains of South America, the proportions of the larger groups are : — 



