ANNOTATIONS AND ADDITIONS. 129 



tiana reaches on the sub- Himalayan mountains a height of 

 5000 English feet. (Wallich, Plantse Asiatics, Vol. iii. 

 Tab. 211.) 



If we look for the extreme geographical limits of palms, 

 (which are also the extreme climatic limits in all the spe- 

 cies which inhabit localities but little raised above the 

 level of the sea), we see some, as the date-palm, the Cha- 

 maerops humilis, C. palmetto, and the Areca sapida of 

 New Zealand, advance far into the temperate zones of 

 either hemisphere, into regions where the mean tempera- 

 ture of the year hardly equals 11. 2 and 12. 5 Reaumur 

 (57.2, and 60.2 Fahrenheit). If we form a series of culti- 

 vated plants or trees, placed in order of succession accord- 

 ing to the degree of heat they require, and beginning with 

 the maximum, we have Cacao, Indigo, Plantains, Coffee, 

 Cotton, Date-palms, Orange and Lemon Trees, Olives, 

 Sweet Chestnuts, and Yines. In Europe, date-palms (intro- 

 duced, not indigenous) grow mingled with Chaimerops 

 humilis in the parallels of 43J and 44, as on the Genoese 

 Rivera del Ponente, near Bordighera, between Monaco a: id 

 San Stefano, where there is an assemblage of more than 

 4000 palm -stems; and in Dalmatia round Spalatro. It is 

 remarkable that Chainserops humilis is abundant both at 

 Nice and in Sardinia, and yet is not found in the island of 

 Corsica which lies between those localities. In the New 

 Continent, the Chamserops palmetto, which is sometimes 

 above 40 English feet high, only advances as far North as 

 34 latitude, a difference sufficiently explained by the in- 

 flexions of the isothermal lines. In the Southern hemi- 



VOL. n. 



