4l6 A ZOOCxEOGRAPHIC SCHEME FOR THE MID-PACIFIC, 



Such data as I have suggest that the distribution obtained in 

 the Eastern Pacific woidd be described by concentric zones of 

 which the outer would be attained only by the strongest swimmers. 



Mr. T. Whitelegge has pointed out to me that the Australian 

 starfish, Asterina exigua, never passes through a free pelagic 

 stage, but goes through all stages of development on the rock on 

 which the egg is laid and to which it adheres. I cannot, however, 

 divide the Echinodermata by similar and opposite habits, suffi- 

 ciently to draw any conclusions from them. 



The abundance of Crustacea at Funafuti agrees with their larval 

 capacity of swimming. The same may be said of the occurrence 

 there of Enteropneusta, Gephyrea and Actinozoa. The genera of 

 Reef Corals diminish markedly in number from west to east. We 

 noticed the absence from Funafuti of many genera usually' common 

 and conspicuous on continental islands, such as Galaxea. 



Too few examples were obtained at Funafuti of the fauna of 

 the deep sea to admit of much discussion. The interesting Palu, 

 Ruvettus pretiosus, however, supports the opinion that a general 

 uniformity prevails over vast areas, if not indeed all round the 

 world, among abyssal animals. 



Our increased knowledge develops distinctions more than 

 affinities between the Central Pacific and tropical Atlantic. But 

 the list of species either closely related in or common to both 

 oceans has been lately enlarged, both among deep and shallow 

 water forms. Willey has commented on the affinity between 

 Asymmetron caudatum from the Louisiades, and A. lucayanum 

 from the Bahamas.* Before its discovery at Funafuti, the sponge 

 Hipjjospongia dura was only known from the Atlantic coast of 

 North America. The fish Ruvettus pretiosus is now shown to be 

 common to both oceans, and the new Brachiopod from Funafuti 

 finds a close ally in Thecidium harretti from the West Indies. I 

 have drawn attention to the relation of Iphitus tubercidatns, 

 Watson, from the West Indies, and my Mecoliotia halligani from 

 Funafuti. Acanthogorgia niU7'icata, described by Verrill from 



* Willey — Quart. Journ. Micro. Sci. xxxix. 1896, p. 220. 



