V MOUNT SEATURA 65 



vegetated " talasinga " region the conformation of the land is well 

 displayed. Broad, deep and nearly parallel valleys, separated by 

 level-topped spurs and occupied by the Lekutu and its tributaries, 

 score the mountain's slopes. The prevailing rocks are blackish- 

 brown olivine-basalts and porphyritic basaltic andesites, such as 

 occur around the other parts of Seatura ; but grey olivine-basalts 

 also occur, possessing opaque plagioclase-phenocrysts and looking 

 like porphyrites. They are essentially holocrystalline and are pro- 

 bably more deeply situated than the other basaltic rocks. They 

 are referred to genera 26 and 38 described on pages 261, 263, and 

 have a specific gravity of 275 — 2'83. Dark doleritic basalts distinct 

 from all the others are exposed in places. 



A good idea of this region may be obtained by following the 

 road westward from Tavua on the head-waters of the Sarawanga 

 River to Wailevu on the westernmost tributary of the Lekutu 

 River, a distance of about 6 miles. Leaving Tavua one at once 

 begins to ascend and cross the long spur that descends from 

 Seatura and divides the valleys of these two river-systems. On its 

 slopes are exposed much decomposed blackish basalts possessing 

 scanty olivine and showing large porphyritic crystals ofplagioclase. 

 They have a specific gravity of 2'84 and are assigned to the 

 porphyritic sub-genus of genus 25 (page 259). At the summit, 800 

 feet above the sea, occur blocks of a grey holocrystalline basalt 

 with scanty olivine and semi-opaque plagioclase-phenocrysts 

 referred to genus 26 and having a specific gravity of 276. It 

 appears to form the axis of the spur. Descending to the main 

 Lekutu River, just below Kavula, where the elevation is about 300 

 feet above the sea, one observes exposed in mass in the river-bed 

 a dark semi-ophitic doleritic basalt similar to the doleritic rocks 

 without olivine prevailing on the coast between Wailea Bay and 

 Lekutu (see page 50), but differing in the absence of felspar- 

 phenocrysts. It displays a considerable amount of opaque inter- 

 stitial glass and is assigned to genus 12 of the augite-andesites 

 (page 275). The specific gravity is 278, but there are a few 

 minute irregular cavities in its substance. 



On leaving Kavula one crosses another of the Seatura spurs at a 

 level of 650 feet, descending then into a smaller river-valley occupied 

 by a tributary of the Lekutu, on the banks of which lies the village 

 of Nawai, 350 feet above the sea. Then another spur is crossed at 

 an elevation of 450 feet and the descent is made into the valley of 

 the Wailevu tributary of the Lekutu. Crossing the valley, which 

 at the town of Wailevu is elevated 300 feet, one rises to a height 



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