214 University of California Puhlications in Botany [Vol. 6 



also on Charles ; and Hood is by no means as closely linked geograph- 

 ically to Charles as Narboroiigh is to Albemarle. Again, therefore, 

 location appears to he of only subsidiary potency. 



HOOD 

 The bonds between all the southeastern islands are revealed again 

 by Hood. Thus, Albemarle fifty-eight, Charles sixty-six, Chatham 

 sixty ; and adjacent Gardner thirty -seven, but four more distant islands 

 of similar floral range, twenty-nine to sixteen. With Indefatigable, 

 possessing 193 species, Hood shares forty-nine ; with James, possessing 

 224 but lying on the farther side of Indefatigable, forty-seven. The 

 narrowness of the difference is as significant as its existence. Duncan 

 (103), near Indefatigable, has forty-five Hood species; Abingdon 

 (119), far to the north, only thirty-five; Narborough (eighty), twenty- 

 six. Barrington, on the Hood side of Indefatigable, has twenty-nine 

 Hood forms out of a total of forty-eight ; Seymour and Jervis. on the 

 James side of the same island, twenty-six out of fifty-two and sixteen 

 out of fortv-two. 



SEYMOUR 

 Seymour is a small island, or rather pair of islets, separated from 

 the north shore of Indefatigable by the narrowest and shallow^est of 

 straits. 73 per cent of its species, or thirty-eight out of fifty-two, are 

 found on Indefatigable. For Charles and Chatham to the southwest, 

 the figures are the same ; for Albemarle and James to the west, only 

 thirty-four and twenty-seven. Again it is apparent that specific 

 abundance is the most influential cause in the establishment of inter- 

 island relationships, and that proximity, especially when close, comes 

 second. As a third factor we can add the greater potency of the south- 

 east than of the remainder of the archipelago, especially upon the 

 central province. Thus Hood has twenty-six Seymoiir species, to 

 fifteen on Narborough and twenty-three on nearer and more varied 

 Duncan ; Barrington and Gardner show nineteen and twenty Seymour 

 identities, Bindloe and Jervis only eleven and thirteen. 



BAERINGTON 

 I have heretofore reckoned Barrington as one of the smaller central 

 islands, on the basis of its geographical situation; but its affinities 

 tend somewhat to the southeastern group, towards which it lies off 

 Indefatigable. Thus : 



