74 



A NATURALIST IN THE PACIFIC chap. 



Quarterly Current Charts ; also Encyclopaedia Britannica, vol. i8, 

 p^ ii8). 



The most serious objection from the botanist's standpoint 

 against such a view as that of Dr. Hillebrand is the absence from 

 Hawaii of most of the shore-plants that we should expect the 

 currents to have brought from the Old World. It is also evident 

 that as far as the currents are concerned the Hawaiian Islands are 

 far more likely to receive littoral plants from America than from 

 the Old World. Though no tropical drift has yet been found 

 stranded on the coasts of these islands, yet it is not unlikely that 

 future investigators may find some seed-drift from Central America 

 on the most southerly coasts of the group, as on the south-east 

 shores of the large island of Hawaii. It would only be stranded in 

 the winter months and then probably in small quantities. 



Summary of the Chapter. 



(a) Since the effective operations of the currents are limited to 

 the shore-plants with buoyant seeds or fruits, such plants forming 

 but a small proportion of any flora, it must be acknowledged that, 

 numerically speaking, the results of the dispersing-agency of the 

 currents on plant-distribution in general are but slight. 



(d) Yet the importance of the subject is by no means to be 

 measured by a numerical scale of results, a line of inquiry being 

 here opened up leading to fields of investigation full of promise for 

 the student of plant-distribution. 



(c) Whilst dealing with the relation between the distribution 

 of shore-plants and the arrangement of the currents, it is quite 

 legitimate to discuss the currents of the Pacific from the point of 

 view of the botanist, who, after all, must take his cue from the 

 drifting seed and the resulting distribution of the plant. 



(d) The shore-plants of the Pacific islands that are dispersed by 

 the currents being mainly Indo-Malayan in origin, it follows that 

 they have extended eastward over the Pacific to the Tahitian 

 islands against the stream of the South Equatorial Current and 

 against the trade-wind. It is, however, shown that they could 

 have availed themselves of the interval between January and 

 March when the North-west Monsoon reaches the Pacific. 



(e) It is claimed that whilst the mangroves and their associated 

 plants have for the most part entered the Pacific by the Melanesian 

 route through the Solomon Islands, the beach-plants have also 

 followed the route through Micronesia by the Caroline, Marshall, 

 and Ellice Groups. 



