lis Transactions. — Botany. 



Crow, six miles from Bealey, which place experienced fine 

 weather the while, and at the same time the downpour on 

 the high ranges added a considerable increase of water to the 

 river. It is quite a common sight to see a heavy storm in 

 progress up the Waimakariri while the sun shines brightly at 

 Bealey. On Arthur's Pass I have observed heavy rain, while 

 down the Bealey Valley, half a mile away, it was quite fine. 

 This great difference between the eastern and western rain- 

 fall (see above, " Meteorology ") has written its mark most un- 

 mistakably upon the vegetation. A line can be drawn which 

 certain plants do not cross usually, and marking what I 

 should take to be the average eastern limit of the north- 

 western rain, and which separates, though not sharply, the 

 district into two great climatic regions — viz., the western and 

 the eastern. 



Throughout this and other papers dealing with the same 

 subject I purposely refrain from speaking dogmatically as to 

 the range of plants. The distribution of New Zealand plants 

 is still too imperfectly known to allow definite statements to 

 be made, and most of such that have been published up to the 

 present are not of much scientific value. Ranunculus lyallii, 

 a common western subalpine plant, and one which would not 

 be thought to exist on the dry eastern hills, is found in an 

 isolated station near Lake Lyndon. Metrosideros lucida, 

 another western plant, occurs on dry rocks at Broken Hill.* 

 Celmisia lyallii, a most typical eastern plant, with, according 

 to Diels, the structure of a steppe grass {loc. cit., pp. 265 and 

 268), has been collected in the neighbourhood of Cook Eiver, 

 Westland, by Mr. Wilson, formerly District Surveyor, Hoki- 

 tika. These extreme cases show that it may be possible to 

 find any eastern plant in the western region, and vice versa, 

 in one or more isolated stations, and the same reasoning applies 

 to north and south limits and altitudinal range for New Zea- 

 land plant geography generally. But this should not hinder 

 us from designating certain plants as "eastern," "western," 

 "northern," "southern," "alpine," " lowland," and the like 

 with perfect propriety. The other climatic divisions of these 

 two regions depend upon altitude, and may be classed as "low- 

 land," "lower mountain," "subalpine," and "alpine." All 

 four occur in the eastern region, but only the two latter to 

 any extent in the western, so far as the Waimakariri system 

 is concerned. The Trelissick basin, a part of the eastern 

 lower mountain region, almost forms a distinct climatic 

 region, owing to its peculiar position with regard to the 



* Another station in this district is the forest near Patterson's 

 Creek, Mount Torlesse, whence I have received specimens collected by 

 Mrs. J. G. L. Scott. 



