CHAP. XIX THE MADAGASCAR GROUP 445 



species. In tlie Seychelles, too, the indigenous flora has 

 been almost entirely destroyed in most of the islands, 

 although the peculiar palms, from their longevity and 

 comparative hardiness, have survived. Mr. Geoffrey Nevill 

 tells us, that at Mahe, and most of the other islands visited 

 by him, it was only in a few spots near the summits of the 

 hills that he could perceive any remains of the ancient 

 flora. Pine-apples, cinnamon, bamboos, and other plants 

 have obtained a firm footing, covering large tracts of 

 country and killing the more delicate native flowers and 

 ferns. The pine-apple, especially, grows almost to the tops 

 of the mountains. Where the timber and shrubs have 

 been destroyed, the water falling on the surface im- 

 mediately cuts channels, runs off rapidly, and causes the 

 land to become dry and arid ; and the same effect is 

 largely seen both in Mauritius and Bourbon, where, 

 originally, dense forest covered the entire surface, and 

 perennial moisture, with its ever-accompanying luxuriance 

 of vegetation, prevailed. 



Flooxt of Madagascar Allied to that of South Africa. — In 

 my Gcogra'phical Distribution of Animals I have remarked 

 on the relation between the insects of Madagascar and 

 those of south temperate Africa, and have speculated on a 

 great southern extension of the continent at the time when 

 Madagascar was united with it. As supporting this view 

 I now quote Mr. Bentham's remarks on the Compositse. 

 He says : " The connections of the Mascarene endemic 

 Compositse, especially those of Madagascar itself, are 

 eminently with the southern and sub-tropical African 

 races; the more tropical races, Plucheinese, &c., may be 

 rather more of an Asiatic type." He further says that the 

 Composite flora is almost as strictly endemic as that of 

 the Sandwich Islands, and that it is much diversified, with 

 evidences of great antiquity, while it shows insular char- 

 acteristics in the tendency to tall shrubby or arborescent 

 forms in several of the endemic or prevailing genera. 



Preponderance of Ferns in the Mascare7ie Flora. — A 

 striking character of the flora of these smaller Mascarene 

 islands is the great preponderance of ferns, and next to 

 them of orchidese. The following figures are taken from 



G G 2 



