OCEANIC HYDROZOA 25 



till 1 858, under the name of " The Oceanic Hydrozoa : 

 a Description of the Calycophoridae and Physophoridae 

 observed during the Voyage of H.M.S. Rattlesnake, in 

 the years 1846-1850." To this classical work, which 

 gives a detailed and comparative treatment of a difficult 

 and then little-known group, and which is dedicated to 

 Sir John Richardson, M.D., F.R.S., his old chief at 

 Haslar, Huxley wrote a Preface, summarizing the diffi- 

 culties that had prevented earlier publication, and acknow- 

 ledging his indebtedness to MacLeay of Sydney, Edward 

 Forbes, and others. 



The following " Extract from a Memorandum by the 

 Lords Commissioners of the Admiralty prefixed to the 

 first edition of the • Manual of Scientific Enquiry pre- 

 pared for the use of Her Majesty's Navy,' edited by 

 Sir J. F. W. Herschel, and published in 1849" is placed 

 at the head of the Preface : — 



" It is the opinion of the Lords Commissioners of the 

 Admiralty that it would be to the honour and advantage of the 

 Navy and conduce to the general interests of Science, if new 

 facilities and encouragement were given to the collection of 

 information upon scientific subjects by the officers, and more 

 particularly by the medical officers, of Her Majesty's Navy, when 

 upon foreign service. . . And it will be for their Lordships 

 to consider whether some pecuniary reward or promotion may 

 not be given to those who succeed in producing eminently useful 

 results." 



And from the Preface itself the following extracts are 

 worth quoting : — 



" The facts are these. I made a good many observations 

 during our cruise, and sent home several papers to the Linnean 

 and Royal Societies ; but of these doves, or rather ravens, 

 which left my ark, I had heard absolutely nothing up to the 

 time of my return ; and, save for the always kind and hearty 

 encouragement of the celebrated William MacLeay, whenever 



