XXVII LORANTHUS 383 



species-making. The berry-like fruits contain an abundance of 

 minute seeds, half a millimetre in size, which, when rendered 

 adhesive by adherent pulp, might readily stick to feathers, or they 

 might pass unharmed through the alimentary canal of a bird. It 

 is noteworthy that amongst the plants regarded by Prof. Penzig as 

 introduced by frugivorous birds into Krakatoa since the eruption 

 is a species of Melastoma. 



Few genera in these islands would better repay a careful study 

 of their species with regard both to the influence of station on 

 specific characters and to the question of " mutations " than 

 Ophiorrhiza. I found the three Fijian species of this Rubiaceous 

 genus so often in close association, that I cannot doubt there 

 is some connection between them. Seemann and Gray, indeed, 

 characterise two of them as confluent species. The island of Tahiti 

 alone possesses five peculiar species, and it is evident that this 

 island has been a centre of development for species of Ophiorrhiza, 

 just as Samoa has become the birthplace of many species of the 

 Urticaceous genus Elatostema, The minute angular seeds of 

 Ophiorrhiza would probably be transported in a bird's feathers or 

 in adherent soil. As my experiments showed, they do not become 

 adhesive when wet. 



The genus LORANTHUS as distributed in the South Pacific has 

 already been briefly noticed. There is a species confined to the 

 Tahitian region, and there is another peculiar to Samoa, whilst one 

 widely-ranging species, L. insularum, that connects these regions 

 together, reaching east to Rarotonga, is closely related with the 

 Tahitian species. There was no doubt originally a single poly- 

 morphous plant that ranged over the tropical South Pacific. With 

 regard to the mode of dispersal of the seeds of this genus of 

 parasites, I should at once refer to the systematic and careful 

 observations made by Mr. F. W. Keeble in Ceylon {Trans. Lzim. 

 Soc, V. 1 895-1901). He formed the opinion that the seeds of 

 Loranthus usually reach their host without passing through the 

 alimentary canal of a bird, being merely wiped off its bill. This 

 method would never carry the seeds to Tahiti or even to Fiji ; and 

 since this observer remarks that, although most of the seeds in the 

 droppings were completely rotten, some of them " possibly pass 

 through the gut uninjured," we may accept this possibility as 

 sufficient for the purpose of dispersal in the Pacific Ocean. 

 Mr. Keeble notes the observation in Teil 3 of Engler's Die 

 Natiirlichen Pfianzotfamilien that the seeds may germinate after 

 passing through a bird's intestine ; and we may therefore infer 



