﻿240 Transactions. — Botany. 



ground by road-sides in Otago." It is certainly desirable to ascertain 

 whether tlie typical form exhibits the same power of rapid increase as the 

 variety. In the North Island the variety is recorded from the East Coast on 

 Mr. Colenso's authority, but I cannot learn that it exhibits the strongly marked 

 facility of propagating itself which it manifests in the south. The only locality 

 in which I have collected it is on the G-reat Barrier Island, where, in 1867, it 

 was rather plentiful on a small patch of ground at Puriri Bay, but was not 

 observed elsewhere ; strange to say on searching the locality in March last, I 

 failed to find a single specimen ! while the typical form appeared to have 

 neither increased nor diminished since my previous visit. 



The peculiar eastern distribution of the variety Dryandri is certainly singular, 

 and taken in conjunction with its excessive abundance and rapid increase in 

 the south may possibly justify suspicion as to the exotic origin of this particular 

 form ; but, unless supported by more dii-ect evidence, this is quite inadequate to 

 warrant a positive conclusion on the subject, especially in the absence of any 

 similar increase in the north, with its more advantageous climatal conditions. 

 In no case can this afiect the question of the introduction of the typical form ; 

 even should it be proved that this exhibits in the south the rapid diff'asion 

 which is so strongly marked in the variety, the fact will still remain that 

 during actual observation, extending over thirty years, the peculiarity has not 

 been evidenced in at least two-thirds of the colony. 



But arguments in favour of exotic origin, based, as in the present case, 

 solely upon the abundance and rapid increase of a plant in certain localities, 

 cannot in any case be considered conclusive in the face of the remarkable 

 increase exhibited by plants whose nativity is xmquestioned. Mr. Travers 

 himself has placed a marked instance on record : I select it chiefly from its 

 occurring in the same district as the subject of this paper. In the article from 

 which I have already quoted, Mr. Travers states that " Azolla rubra is 

 rapidly increasing, and utterly impedes the progress of draining in the lower 

 and more level tracts of the country." A startling phenomenon, as compared 

 with the conditions under which this plant occurs in the north ; yet, I imagine, 

 no one would think of suggesting the great abundance and rapid increase of 

 Azolla, in the province of Canterbury, as evidence of its exotic origin in that 

 province, much less in the colony at large. 



It is singular that Mr. Travers should adduce the opinion of the natives as 

 evidence of the exotic origin of the Knot-grass, when he has seen fit to reject it 

 with regard to the introduction of the Flesh-fly, of which he has given so intei'- 

 esting an account in the last volume of the Transactions. My own experience 

 has led me to the conclusion that native evidence on questions of this kind is 

 usually worthless, and it is commonly stated by the old residents and 

 missionaries that the Maoris of the present day are greatly inferior to those of 



