520 CALIFORNIA ACADEMY OF SCIENCES. 



extreme peculiarity of its fauna is the result partly of pro- 

 gressive divergence and partly of many forms saved by isola- 

 tion. In the case of the coast islands of California, the 

 separation is comparatively recent — there has not been time 

 enough for very great divergence by modification. The 

 peculiarity of its flora is due almost wholly to species saved 

 by isolation . 



In conclusion I would say, that this short paper is intended 

 merely as as incentive to future investigation and pointing 

 in the direction which it ought to take. Before the views 

 above presented can be definitely established, there must be 

 further investigations, first, on the relation of the island 

 flora to that of the mainland; second, on the relation of the 

 flora of California to that of adjacent points from which it 

 may have been originally colonized; third, and especially, 

 must we have fuller knowledge of the indigenous flora of 

 California in Pliocene times. 



