﻿Kirk. — On the Flora of the Auckland Isthmus. 229 



The lists of Mosses and Hepaticse, as might be expected, are the most com- 

 plete, and comprise many interesting forms. Hypnum infiatum, one of the 

 handsomest mosses in our flora, occurs here, although sparingly. Gampylopus 

 appressifolius, which appears to be rare in other parts of the colony, is abundant 

 in this limited district. Didymodon papillatus is plentiful alike on the scoria 

 hills, the stiff clays, and the sands of the sea shore. Bryum curvicollum is 

 common wherever fresh water trickles down the sea cliffs. Several species are 

 extremely local ; Dicranum elathratum is confined to a solitary habitat : 

 Hedwigia ciliata, a common European moss, is restricted to less than a single 

 square yard in its only known habitat in the North Island. Anomodon Huttoni, 

 n.s., (originally discovered at Omaha, possesses special interest as being the 

 only member of the genus hitherto discovered in the Australian Colonies. It 

 appears to be confined to New Zealand, but has not been found south of 

 Auckland. 



Gales from certain points often deposit particular species of marine Algse 

 on the shores of the harbour ; thus, after easterly gales Mesogloia intestinalis 

 is often found in large quantities in Freeman's Bay, accompanied by the 

 curious mollusc, Solenomya Australis, northerly gales often bring Landsburgia 

 quercifolia, and Codium tomentosum. Tidal rocks in the harbour form a 

 favouiite habitat for Horviosira Billardieri, and rocky tidal pools exhibit a rich 

 growth of Gorallina and Jania. One or two species of Polysiphonia, and 

 possibly a Bostrychia, are found in situations where they are partially exposed 

 to the influence of fresh water. It must be allowed that the impuiities neces- 

 sarily washed into the harbour from the large city which adorns its banks are 

 unfavourable to the growth of the most attractive members of this order. The 

 tei'restrial and fresh-water Algse are few in number, and unimportant ; the 

 paucity of the latter is only what might be expected from the absence of any 

 lai'ge streams or canals in the district, and the rarity even of ponds. 



Many of the Lichens are extremely local in their habitats. Of the numerous 

 GraphidcB collected in the district by Dr. Knight, I have only observed two 

 or three sj)ecies of Opegrapha and Arthonia. This is to some extent owing to 

 the destruction of the low-growing shrubs and small trees, which, until within 

 the last six or seven years, adorned many spots on the scoria fields, and 

 partially clothed the base of several of the volcanic hills. 



The interesting question of the introduction and diffusion of cryptogamic 

 plants in new countries has been suggested by the occurrence of Bryum 

 argenteum, a common European moss, under jDeculiar cii^cumstances. Although 

 abundant in this district it appears to be extremely rare elsewhere in the 

 colony — the only recorded instance of its discovery being by Dr. Lyall, who 

 obtained a scrap amongst other mosses collected by him in the South Island 

 more than twenty years ago. It is not included in Dr. Lindsay's " Catalogue 



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