CH. Ill] ENDEMISM, AGE AND AREA 25 



C. elongatus was a local adaptation, i.e. a success, but if so, why- 

 did it not have a different habitat from C. harhatust Others 

 offered the reverse explanation, and said that it was a relic of 

 previous vegetation, i.e. a failure. But again, why did it continue 

 to grow in the same places as C. harhatus, the most widespread 

 and successful of the Coleil Why was it not killed out? And why 

 was it morphologically distinct from all other Colei, with a few 

 exceptions in Africa? Had a pendulous inflorescence with stalked 

 flowers given rise to a normal Labiate one, which otherwise 

 characterises much of this genus of 150 species of tropical Asia 

 and Africa ? And how did the calyx change from five equal teeth 

 to two lips, one presenting four teeth, one one? Regular variation 

 in a calyx would always affect the teeth equally; a two-lipped 

 condition could only be the result of some sudden change. The 

 final refuge of the natural selectionist is usually to say that the 

 peculiarities must have been useful at some other time, or at 

 some other place. But the conditions upon the summit of Riti- 

 gala, and in all probability in the country between it and the wet 

 zone, had not altered since the Tertiary, and there was no sign of 

 C elongatus anywhere else, while its most successful and closely 

 related rival, C. harhatus^ was upon the same summit, in similar 

 places, and about equally common. Neither of the diametrically 

 opposed solutions offered by the natural selectionists would hold 

 water, especially as no adaptational value could possibly be read 

 into either inflorescence or calyx, whereas the problem was easily 

 solved by imagining C. elongatus to have arisen by a single 

 mutation from C. harhatus. And why was there another endemic 

 in the mountain mass of the wet zone also? Was it a case of 

 isolation resulting in a new species upon Ritigala? This was the 

 only probable explanation other than that of mutation which has 

 been offered, and as the wet-zone endemic has neither the equal 

 sepals nor the pendulous inflorescence, marked mutation must 

 have gone on. There was no opening for natural selection, even 

 could it have produced such differences among the few dozen 

 plants of both species upon the summit of Ritigala. It was also 

 clear that upon the principles of natural selection, as altered by 

 Darwin after the destructive criticisms of Fleeming Jenkin (21), 

 there was not room enough upon the summit of Ritigala to allow 

 of the development of even one endemic, to say nothing of two or 

 three, or of the surprising fact that the most common and wide- 

 spread species of Coleus was also living there with the local 

 endemic, and in the same or similar places. 



