PREFACE ix 



When the " Challenger " Expedition visited the group in 1875 

 some geological collections were made which were described by 

 Prof. Renard in the second volume on the " Physics and Chemistry " 

 of the expedition. No collections, however, were made in Vanua 

 Leva. In 1878 Mr. John Home, Director of the Botanic Gardens 

 at Mauritius, made some important observations on the geological 

 structure of this island and of other parts of the group, which he 

 published in his account of the islands given in " A Year in Fiji." 

 No collections were obtained by him ; but prominence is given to 

 his observations by Dr. Wichmann and others. Like Dana in the 

 case of the acid volcanic rocks, Mr. Home has forestalled me in 

 his conclusion that Vanua Levu amongst the other larger islands 

 has been formed mainly of the products of submarine eruptions. 



The visit of Prof A. Agassiz to Fiji in 1897-98 gave a fresh 

 impetus to its geological investigation. We are indebted to him 

 not only for his own extensive memoir on the islands and coral 

 reefs of this group, but also for the subsequent important explora- 

 tions of Mr. E. C. Andrews and Mr. B. Sawyer in Viti Levu and 

 the Lau Islands. These two gentlemen have since published 

 a short paper on the caves of these islands. Mr. Eakle has 

 described the volcanic rocks collected during the visit of Prof. 

 Agassiz. It is, however, noteworthy that, although the collections 

 were made in Viti Levu, Kandavu and in many other of the 

 smaller islands, Vanua Levu is not represented. Mr. Eakle's 

 conclusion that basic andesites and basalts are the characteristic 

 rocks of the region, the augite-andesites predominating, would 

 apply to Vanua Levu in great part. This island possesses also in 

 fair amount hypersthene-andesites and dacitic or felsitic andesites, 

 which are very scantily represented in the collections examined by 

 Mr. Eakle. In connection with the quartz-porphyries and trachytic 

 rocks which also occur in Vanua Levu, it should be observed that 

 Mr. Andrews describes a rhyolite from Suva in Viti Levu. Unlike 

 Viti Levu, Vanua Levu displays but a small development of 

 plutonic rocks. 



In conclusion it should be pointed out that much remains to be 

 done in the geological exploration of this island, and that I would 

 have spent a third year in this task much to my profit. Still I 



