148 



Unless specially mentioned, I am not aware of the occurrence of any of 

 tlie foregoing beyond the reach of tidal waters. 



No mention is made in the foregoing list of two or three littoral plants of 

 doubtful identification, or of a few species, such as Potamogeton 2yectinatus 

 and Zannichellia jKilustris. which are found indifferently in fresh or brackish 

 water in Europe, but are of extreme rarity in New Zealand, and occur in 

 the Waikato in company with known littoral species ; and it should be 

 remembered, that the advanced period of the season at which these observations 

 were made was unfavourable for field work, as in their decaying state several 

 of the smaller growing kinds were doubtless overlooked in some of the 

 localities visited, and other species may have escaped notice altogether. 



It is readily admitted that littoi-al plants may occasionally be found in 

 inland situations from accidental causes, but in the present case the number of 

 species, and the wide area over which they collectively extend, afford forcible 

 proof that the cause of their growth must be found in the district having been 

 formerly a shallow estuary, probably connected with the Frith of the Thames. 

 Beating in mind, that with each rising of the river the current at first runs 

 swiftly into the lakes of Lower Waikato from the river, instead of from the 

 lakes into the river, a ready explanation is afforded of the way in which these 

 littoral plants have become established there. It is difiicult to imagine that a 

 plant of salt marshes, as Scir-pus onaritimus, could be carried from the mouth 

 of the river, against a rapid current, for a distance of one hundred miles along 

 its banks, and diffused over the fresh water lakes and swamps of a large extent 

 of country besides. It is easy of comprehension how, if introduced from the 

 Frith of the Thames, it would become established in the marshes, etc., on the 

 retirement of the river to its present bed, and carried downwards until it again 

 met the tidal water on the western coast. 



There can be little doubt that a careful examination of the country between 

 the Frith of the Thames and Middle Waikato, would result in the collection of 

 additional evidence on this interesting subject. 



Art. XXVI. — On the Flora of the Isthmus of Auckland and the Takapuiia 



District. By T. Kirk. 



\_Reacl hefore the Aucldand Institute, August 8, 1870.] 



PART I. 



In this paper it is intended to briefly delineate the Flora of the immediate 

 vicinity of Auckland, so far as regards the Phsenogams and higher ordei's of 

 Acrogens. The lower Acrogens and the Thallogens will, it is hoped, form the 

 subject of a subsequent paper. 



