MOLLIISCA OF THE ' CHALLENGEE ' EXPEDITION. 507 



in spirit, the handling of which, with the sorting into bottles, and 

 still more the examination and even partial dissection of the ani- 

 mals, require very much more time. Some 300 of these have, 

 however, even already been sorted out. 



In all, over 2000 separate lots, including from 1200 to 1500 

 distinct species, have been gone over, separated, put into 

 boxes or bottles, labelled, catalogued, and indexed. There yet 

 remains, indeed, a very great deal to do ; but through it I do, to 

 some extent, see my way. 



Simultaneously with all this, authorities have been consulted, 

 and types in the British Museum and elsewhere, as opportunity 

 offered , have been examined, to determine which of the species 

 under my charge are already known and which are new. 



Any one wlio has experience of such labour, pleasant though it 

 be, will recognize that a very heavy share of work has fallen to me, 

 in which, without much kind help at home, and especially from an 

 early and able pupil of your own, even so much as has been done 

 could not have been accomplished. 



My object now is to make a beginning of publishing, so as to 

 clear my way of any thing I can get off my hands, to be ready for 

 the final publication of the ' Challenger ' Eeports when that time 

 comes, and to secure help now in correcting my mistakes. Need I 

 say that these are inevitable ? To escape them, I should require 

 a universal knowledge of the world's conchology, and a universal 

 library of conchological literature. Very little help in either di- 

 rection is available here in Edinburgh. 



I am very painfully aware that specialists, both in geographical 

 and in scientific groups, will recognize oversights — failures of 

 memory and positive blunders that may seem to them incredible. 

 I very humbly make to them my apology beforehand, and entreat 

 of their good will such help as lies under their hand to give in 

 allowing me to examine specimens of the rarer species, and in 

 sending me copies of papers I may be apt to overlook. Kind 

 help in this direction I have already thankfully to acknowledge. 



The order of publication to be followed now must depend partly 

 on my own convenience, and partly on other exigencies. 



In conclusion, I may just say that the Land-shells I have as yet 

 scarcely touched, that the Brachiopods have been ably com- 

 pleted by Mr. Davidson, and of the Cephalopoda, Pteropods, 

 and Nudibranchs I have been relieved. 



37* 



