264 JWansactions. 



Akt. XXIX. — On the Occurrence of Poa litorosa Cheeseman on Here- 



kopere Island. 



By D. Petbie, M.A., Ph.D. 



[Read before the Auckland Institute, 11th December, i9i^.] 



In the early summer of last year Mr. H. Guthrie-Smith, of Tutira 

 (Hawke's Bay), kindly sent me some live tufts of native grasses from 

 Herekopere Island (off Stewart Island). Among these was a piece that, 

 on flowering this season, has proved to be Poa litorosa Cheeseman, a 

 grass that was thought to be confined to the subantarctic islands of New 

 Zealand. Along with this came a piece of Poa foHosa Hk. f., which the 

 late Mr. Kirk collected on the same island a good many years ago, as 

 well as pieces of two other grasses, one of which is a new species and 

 is described in another paper contributed to this volume. 



This extension of the range of Cheeseman's species is of considerable 

 interest, as it adds an additional link to the already well-known con- 

 nection between the floras of New Zealand proper and of the subantarctic 

 islands. The grass is likely to occur at the Snares. The flora of this 

 isolated group is still very imperfectly known, and a careful exploration 

 of its botany is urgently needed. 



Art. XXX. — Note on the Pollination of Pi,habdothamnus Solandri 



A. Cunn. 



By D. Petrie, M.A., Ph.D. 



[Read before the Aiickland Institute, 11th December, 1912.] 



In a short paper in vol. 35 of the Transactions I described the mode of 

 pollination in this species, and came to the conclusion that the flowers 

 are pollinated by the agency of birds, though no direct evidence of this 

 was at the time available. It is with much satisfaction that I can now 

 submit such evidence. Mr. M. Fraser, of New Plymouth, who spent his 

 boyhood in the Upper Waipu district of Auckland Peninsula, writes me 

 that in the early days of settlement this shrub grew in great abundance 

 on the loamy river -flats of the Waipu district. He again and again 

 observed the tui visit its flowers to feed on the abundant nectar secreted 

 by them. His attention was specially attracted by the patient and 

 dexterous efforts of the bird to maintain its foothold on the slender 

 naked branches, and its cleverness in swinging its body and twisting and 

 stretching its neck and fluttering its wings till it succeeded in inserting 

 its bill into the flower. The struggle that led to the sucking of the 

 nectar amply explains the occasional rupture of the corolla, to which 

 I appealed as evidence that the flowers are pollinated by birds. Since 

 the original paper was written I have never lost an opportunity of 

 examining the flowers of this interesting plant, and have seen nothing 

 to conflict with the account there given of the remarkable mechanism 

 that makes auto-pollination impossible. It is one of the most beautiful 

 adaptations to prevent auto-pollination that I am acquainted with. 



