412 Transactions. — Geology. 



lana, Tralia costelkiris, Chione stutchburyi, and Mesodesma 

 novce-zelandia. The Crustacea are : Crabs, shrimps, and sand- 

 hoppers. 



These sea and salt-marsh shells are being driven gradually 

 seaward year by year by the encroaching flood deposits. 

 Tralia costellaris, a curious little member of the family 

 Auriculida, was, before 1897, very plentiful in the salt-weSd 

 on the harbour side of the Wharerangi Road. But that 

 flood practically exterminated it from this area ; it is now 

 very scarce, and is only found on the highest banks of the 

 sea-creeks that run up to the road. It is plentiful enough 

 still at the Petane end of the harbour, where I have found it 

 climbing high on the rush-bushes after rain, reminding one 

 that some tropical species of this family have taken to an 

 inland and forest life as true land-shells. 



The flora of the seaward side of this road is interest- 

 ing only from its contrast to the opposite side. Once past 

 the shooting- butts point, the tide swirls up almost to the 

 roadway, leaving naked on its retreat mats of sea-grass 

 {Zoster a) ; then these harbour shallows shrink to ever- 

 narrowing channels, which lose themselves towards the 

 Wharerangi turn-off in silt-flats given over solely to Sali- 

 cornia and Tngloclnn. 



On the landward, or rather the swamp, side there is 

 much more variety. We get here the typical sea-marsh flora, 

 flourishing on the neck of comparatively dry land that divides 

 the road from a large lagoon. The pioneers of the silt-flats 

 nearer town, Salicornia and Triglochui, are here in abund- 

 ance, with wild celery {Apiiim australe), Samolus littorahs, 

 Selliera radicans, and Mimiilus repens. The weed that 

 chokes the channel is a brackish-water plant, Buppia 

 maritima. 



A-pium australe is the wild celery, so common alike on our 

 coastal cliffs and sea-marshes. It is said that Cook's seamen 

 used this plant as an antidote to scurvy. Samolus littoral-is 

 is of interest from being the one and only representative of the 

 primrose family native to New Zealand. Its pale-pink flowers, 

 which it bears in great profusion, relieves the somewhat 

 sombre colouring of this roadside during the early months of 

 summer. Mimulus repens, a curious little creeping ally of the 

 snapdragon, is only to be seen at one place by the roadside, 

 and that nearly opposite the Wharerangi turn-off ;♦ but it is 

 very plentiful in other parts of the swamp, notably round the 

 wetter portions of the paddocks of the North British Freezing- 

 works. 



The work of the flood of 1897 has been given as an exampie 

 of natural reclamation. Turning to the artificial, it is interest- 

 ing to watch the inroads made by man by means of draining 



