Speight, Cockaynio, fiAiNc. — Mount Arroii'unn'fh Disfricf. 355 



Bog suiTouiidod by steppe can be seen at various stages of develop- 

 ment. In one place on Prospect Hill (about 900 m. altitude) the hollow- 

 clearly indicates a former tarn in a rock-basin, but the whole is now Sphag- 

 num bog, while in another place, close by, a tarn is in course of occupation 

 by bog. Let us first consider the tarn. 



This, where it joins the bog, is about 30 cm. deep. The water, then, 

 will get quite warm on a hot summer's day. Growing in it is Elaeocharis 

 Cynninghmnii ? (slender rush form), Carex ternaria (grasslike sedge), and 

 the Sphagnum moss grows out into the water, its margin unevenly undu- 

 lating. With the advancing moss there is Schizeilema nitens and tussocks 

 of Schoenus pauciflorus, the former also floating on the water just at the 

 edge of the tarn. Drosera arcturi (small herb with short rootstock and 

 reddish linear-ligulate leaves furnished above with glandular hairs) and 

 Carex stellulata are amongst the first plants to settle on the Sphagnum. 

 Tussocks of Danthonia Raoulii also come occasionally right to the front. 

 The grassy and far-spreading Carex Gaudichaudiana is abundant, but it is 

 a later arrival than any of the above. Other plants are Oreobolus pecti- 

 natus (dense small green cushions of distichous stiff short linear-subulate 

 leaves with broad equitant bases), Carex suhdola, Pratia angulata. Drosera 

 arcturi and Carex stellulata are very abundant all over the bog, but there is 

 much less tussock than on the older bog to be next described. 



The bog which has buried the tarn is made up of close masses of Sphag- 

 num, which for the most part is concealed by the grassy Carex Gaudichau- 

 diana. In many parts steppe is virtually installed, as tussocks of Dan- 

 thonia Raoulii are dominant. Where these do not touch there are open 

 spaces occupied by C. Gaudichaudiana, Bulhinella Hookeri var, angusti- 

 folia, Blechnum penna marina, some tussocks of Poa caespitosa, Anisotome 

 aromatica, creeping Gaultheria depressa, a species of Polytrichum, Viola 

 Cunninghamii, Schizeilema nitens and Ranunculus rivularis (where water 

 lies), Celmisia longifolia, Epilobium chloraefolium, Helichrysum. hellidioides, 

 Wahlenbergia saxicola. Here and there, right on the Sphagnum cushions, 

 are rounded low bushes of Dacrydiiim Bidwillii. As is well known, the 

 Sphagnum plants die below and are gradually converted into peat, while 

 their apices continue to grow upwards ; and if the plants which have settled 

 upon the moss are not able to grow upwards at the same rate as the bog, 

 rooting at the same time, they will be eventually buried by the moss and 

 killed. Thus on this particular bog plants of the dwarf taxad, Dacrydium 

 Bidwillii, exhibit various stages of burial, notwithstanding the power this 

 shrub has of extending by means of creeping and rooting prostrate stems 

 furnished with spreading juvenile leaves. On the other hand, the rhizo- 

 matous sedge, Carex Gaudichaudiana, can grow faster than the moss, form 

 a turf, and check its upward growth altogether ; so that the moss in its 

 turn is the vanquished. With the consequent drying of the ground, steppe 

 is by degrees estabhshed, but it must be understood that the first-coming 

 tussocks on the bog-moss are liable to burial, and a growth of these does 

 not of necessity denote the installation of steppe. 



t Growth-forms of Bog. 



The following growth-forms were noted on the bogs of the district : — 

 The number of species in the list of plants is 36 (35 evergreen, 1 summer- 

 green). This would have been greater most undoubtedly had we reached 

 the bogs (1,200 m. altitude) on Mein's Knob. 



12* 



