484 THE GEOLOGY OF THE NEW nEHRIDES, 



Pig. 2. — Hornblende crystal paramorph in magnetite dust and angite micro- 

 lites, from the Wai Bubo andesite; magnified 23 diams. The light 

 central area is part of the original amphibole; for description, see 

 p. 462. 



Fig.3. — Uralite porphyry from North Malckula; magnified 23 diams. The 

 large crystals arc uralite in a dense groundraass. To the left of the 

 section a small crystal with a triangular zone of magnetite is a 

 diametral section through an aggregate similar to that shown in 

 Fig.l; for description, see p. 468. 



Fig, 4. — A felspar glomerule in the Mau basalt; magnified 24 diams. Note 

 the central labradorite, peripheral zone darkened by inclusions, and 

 marginal andesine; for description, see p.463. 



Fig. 5, —The same aggregate under crossed nicols showing the multiple 

 character; magnified 24 diams. 



Plate xxiv. 

 Section along Steep Cxully, Havannah Harbour; showing the character of 

 the terraced limestone veneer and of the andesite foundation-tuffs. 



Plate XXV. 

 Sketch section, slightly generalised, from Cape Tsinone to Losubunu (the 

 highest point in the New Hebrides), South-west Santo; showing 

 the folded Miocene tuffaceous limestones intruded by andesite 

 lavas. At the north-east end of the Section, the site of an old 

 Miocene volcano, the lava-series appears to be quite 5000 feet thick. 

 Toward the left hand side, a small outcrop of the Miocene series, 

 dipping steeply to the S.W., represents the overfolded beds exposed 

 on the Wai Bubo. 



Plate xxvi. 



Generalised Section across the New Hebrides chain. A typical section of 

 the primary Miocene fold-chain is shown in Santo on the left. 

 Note the overfolding of the Miocene series, and extrusion of 

 andesite lavas. Ambrym, one of the islands of the eastern wing, is 

 a great recent volcano, situated probably along an inner wing-fault 

 which has let down the sea-floor considerably between the New 

 Hebrides and Fiji. 



Plate xxvii. 



Map of New Hebrides Group taken from Admiralty charts. Note the east 

 and west wings typified by basic and andesitic lavas respectively; 

 at Efatti the two wings junction, and both series of lavas are found 

 in juxtaposition; further south, after crossing the western land- 

 ridge, the line of basic cones alone remains visible. 



[Printed off "December 18th, 1905.] 



