352 PHYSIOGNOMY OF PLANTS. 



rarely, that in four years we were only twice able to procure blossoms ; 

 once on the unfrequented banks of the Cassiquiare (the arm which 

 connects the Orinoco with the Rio Negro and the Amazons River), 

 and once in the province of Popayan between Buga and Quilichao. It 

 is striking to see plants in particular localities grow with the greatest 

 vigor without producing flowers : it is thus with European Olive-trees, 

 which have been planted for centuries between the tropics near Quito, 

 9000 (about 9590 English) feet above the level of the sea, and also 

 in the Isle of France, with Walnut-trees, Hazel-nuts, and, as at Quito, 

 Olive-trees (Olea europea) : see Bojer, Hortus Mauritianus, 1837, p. 

 291. 



As some of the Bambusaceae (arborescent grasses) advance into 

 the temperate zone, so, within the tropics, they do not suffer from 

 the temperate climate of the mountains. They certainly grow more 

 luxuriantly as social plants from the seacoast to the height of about 

 2560 English feet; for example, in the province de las Esmeraldas, 

 west of the Volcano of Pichincha, where Guadua angustifolia (Bam- 

 busa Guadua, in our Plantes 6quinoxiales, t. i. tab. xx.) produces in 

 its interior much of the silicious Tabaschir (Sanscrit tvakkschira, 

 ox-milk). In the Pass of Quindiu, we saw the Guadua growing at 

 an elevation which we found by barometric measurement to be 5400 

 (5755 English) feet above the level of the Pacific. Nastus borboni- 

 cus is called by Bory de St. Vincent a true alpine plant; he states 

 that it does not descend lower on the declivity of the Volcano in the 

 Island of Bourbon than 3600 (3837 English) feet. This recurrence 

 or repetition as it were at great elevations of the forms characteristic 

 of the hot plains, recalls the mountain group of palms before pointed 

 out by me (Kunthia Montana, Ceroxylon andicola, and Oreodoxa 

 frigida), and a grove or thicket of Musaceae sixteen English feet 

 high (Heliconia, perhaps Maranta), which I found growing isolated 

 at an elevation of 6600 (7034 English) feet, on the Silla de Carac- 

 cas. (Relation hist. t. i. p. 605-606.) As, with the exception of 

 a few isolated herbaceous dicotyledones, grasses form the highest 

 zone of phasnogamous vegetation round the snowy summits of lofty 

 mountains, so also, in advancing in a horizontal direction towards 

 either pole of the Earth, the phaenogamous vegetation terminates 

 with grasses. 



To my young friend Joseph Hooker, who, but just returned with 



