514 A NATURALIST IN THE PACIFIC ch. xxxiii 



Pacific, and were only set free after the cold period had passed 

 away, when they overran Polynesia. 



(2) Whilst the age of the Conifers is placed in the Mesozoic 

 period, that of the Compositae is accredited to the Tertiary period, 

 and the era of Malayan immigration followed the glacial epoch. 



(3) The suspension to a great extent of the agencies of plant- 

 dispersal in the Pacific in later times is connected with a general 

 principle affecting the whole plant-world. With the secular drying 

 up of the globe the differentiation of climate, bird, and plant have 

 gone on together, the range of the bird being mainly controlled by 

 the climate and the range of the plant being largely dependent 

 on the bird. 



(4) Accepting Hawaii as entirely insular in its history, it is 

 pointed out that the principles deducible from the study of its 

 flora can be applied to the forest-flora of New Zealand, with the 

 exception of the Conifers and some genera that are ancient denizens 

 of Antarctic latitudes, and indicate a remote continental age 

 dating back to the Mesozoic period. It is suggested that the Indo- 

 Malayan element in its flora arrived there during the glaciation of 

 the northern hemisphere. 



(5) Insects and bats have probably been effective agents in 

 seed-dispersal in the Pacific, and it is shown that sea-birds carry 

 seeds in their stomach and intestines as well as in their feathers. 



(6) It is shown that birds of the grouse family, gulls, and geese 

 are active seed-dispersers in cold northern latitudes, and that the 

 discussion of their influence in stocking Spitzbergen with its plants 

 reproduces many of the points of the controversy concerning the 

 floras of the continental islands of the South Pacific. 



(7) The results of experiments and observations are cited to 

 establish the efficacy of ducks in distributing the seeds of aquatic 

 plants, the seeds ejected in their droppings germinating in a few 

 days or weeks, whilst those remaining in the pond or river often do 

 not germinate for a year or more. 



