INTRODUCTORY REMARKS. 
In the following memoranda I have given such observations as I have 
been enabled to make on the animals of the various genera, brought home 
either by Captain Beechey’s expedition, or by several other voyagers, as 
Captain Lord Byron, Mr. Fryer, and the Rev. Mr. Hennah, who about the 
same time touched at several parts of the world which were also visited by this 
expedition. I have been induced to follow this course, rather than to give 
only a description of the new species discovered by the officers of the expe- 
dition, (as it was my intention to have done when first the specimens were put 
into my hands), because Mr. Sowerby and Mr. Broderip, almost imme- 
diately on the return of the expedition, described many of the new and 
interesting species discovered during the voyage, specimens of most of which 
were given to the Zoological Society by Lieutenant (now Captain) Belcher, 
one of the officers of Captain Beechey’s ship. In my MSS. I had given 
names to most of the species, but I have since substituted those used by the 
above-mentioned gentlemen, that science might not be burthened by the 
many useless names which an opposite course would have produced. 
Many of the descriptions of the animals are from specimens brought home 
by the expedition, and subsequently presented to the Naval Hospital at Haslar 
by Mr. Miller, a most able anatomist, and very accurate observer ; others 
are taken from specimens in the collection of the British Museum ; and very 
many from the collection of Mollusca in the Garden of Plants at Paris, 
where, through the great kindness of M. de Blainville, I was allowed to work 
