H ■ ^ ^ 



-r -■ . ".* 



R. H. COMPTON : GYMNOSPEEMS. 



423 



dissection of exposed land-sTirfaces through weathering. In New Caledonia, 

 for cue reason and another, erosion has had the result of cutting up the 

 island into a number of more or less isolated massifs, separated bj deep 

 valleys— there being no mountain chain of any great extent with a con- 

 tinuous surface above 3000 feet. The montane Conifer islets therefore form 

 a kind of archipelago, of which none can be fairly called the maiidand. 



Tht-re oven appears to be a certain amount of endemism within this 

 archipelago. For instance, Lihocednis amtrocaledonica has hitherto been 



lonn^ii 



it 



seems 



^ 



collccfod only on the Mont Huinboldt-Nekando massif, tl 



probable that further exploration will disclose new situations for this and 



for oth(M' q^ecies of aj>parently restricted areas. 



Wliile this Conifer forest is best developed on the serpentine, other hard 

 rocks also carry a similar, though loss striking, association. On the gneiss 

 of the Panie-Ignambi range in the north of the island the dominant trees 

 above 3000 ft. are Angiosperms, and Conifers are for the most part 



thiidy develoi)edj though local societies {e.g., oi Dacrydium tcuroides) may 

 fee found. 



The lowland Conifers also furnish examples of restricted distribulion, 

 though for less obvious geographical reasons than in the case of the montane 

 i?pecies. For insfance^ Callitrls sulcata is copiously present in the valley of 

 the Kivcr Comboui, and practically absent elsewhere ; and the new genus 

 Callitropsis was only met with in one restricted locality on the banks of the 

 It. du Carcna2;o. 



For the most part, however, the more lowland forms liave a wide distri- 

 bution in the island, explicable by the present or recent continuity of 

 ^suitable habitats. Thus Araucaria Cookii is found all round the coasts, 

 though most abundant in the south ; Agatliis lanceolata occurs in all the 

 lowland serpentine forests in the south; AgatJds Moorei and Aiistrotaxus 

 .spicata occur throughout the forests of moderate altitude in the north j 

 Podocarpus novcc-caledonuc is a constant element of the salicifoliate river- 

 side association in the serpentine districts; Vacry dium Balans(c Viiul Podo- 

 ^arjnis Vieillardii occur, though sparsely, in widely separated lowland 

 localities; AgatJds ovata and Dacrgdhnn araucarioides are frecpient in the 

 serpentine scrub wherever this is developed at moderate heights. 



With two exceptions the New Caledonian Conifers do not form forests in 

 wdiich a single species is donu'nant over wide areas. The excepfions are the 

 **' Comboui Pine'-' (Callitris sulcata)^ which forms pure light forest in the 

 -Comboui Viillcy, and the ^'^Coluuinar Pine^' (Araucaria Cookii)^ which grows 

 in <lense forests on the Isle of Pines and the neighbouring coral and shin<>le 

 islets. A remarkable landscape feature is produced by the presence on the 

 juost exposed and arid serpentine crests of a thin sprinkling of Araucarlas^ 



2h2 



i 



