PREFACE. 



The zoological collections made during the Surveying-voyage of 

 H.M.S. ' Alert ' in the years 1878-82, under the command of 

 Capt. Sir G. Nares and his successor Capt. J. Maclear, -were 

 presented by the Lords Commissioners of the Admirafty to the 

 Trustees of the British Museum. 



A narrative of the voyage has been given by Staff-Surgeon 

 E. W. Coppinger, in his work ' Cruise of the ' Alert ' ' (London, 

 1883, 8vo). 



The principal parts of the Survey, and consequently the 

 Collections, fall into three distinct sections, viz.: — 1, that of 

 the Southern extremity of the American continent; 2, that of 

 the coasts of North-eastern Australia and Torres Straits ; and 

 3, that of the groups of Oceanic Islands in the Western Indian 

 Ocean, situated between the Seychelles and Madagascar. 



The first of these coUeotions has already been reported upon in 

 Proe. Zool. Soc. 1881 ; but the two others surpass it so much 

 in extent and importance as to be quite beyond the scope of a 

 periodical publication, and therefore the Trustees considered it 

 best that a full account of them should be prepared in the form 

 of a separate work. With the exception of the 'Challenger' 

 Expedition, none of the recent voyages has contributed so much 

 to our knowledge of the Littoral Invertebrate Fauna of the Indo- 

 Pacific Ocean as that of the ' Alert,' Irrespective of a number of 

 specimens set aside as duplicates, not less than 3700, referable 

 to 1300 species, were incorporated in the National Collection ; and 



