PREFATORY NOTES. 



These Catalogues are printed in order to make known to Curators 

 of Museums and private Naturalists the present state of my collec- 

 tions, and to invite exchange. 



I shall be glad of any opportunities which may be afforded me of 

 procuring, either by exchange or purchase, species not contained in 

 this list. 



In return for desiderata which may be kindly offered me, I shall 

 be happy to send either Mollusca or, if preferred, animals belonging 

 to other classes of Marine Invertebrata. Of course it will be under- 

 stood that a catalogue which embraces my entire collection necessarily 

 includes a large number of forms of which there are no duplicates. 



Letters should be addressed 



BURNMOOR RECTORY, 



FENCE HOUSES, 



Co. DURHAM. 



The Collections to which these Catalogues refer are in the main 

 confined to the Fauna of Europe, together with that of the Arctic and 

 North Atlantic Oceans, including the seas connected with them. 



The North Atlantic Ocean is here regarded as terminating 

 towards the South at Lat. 35 N ; or at a line drawn from a little to 

 the South of the Straits of Gibraltar on the Eastern, to Cape Hatteras 

 on the Western side. This boundary is adopted as perhaps the best 

 to embrace the Arctic and Temperate regions, and at the same time 

 to exclude the tropical animals of the Gulf of Mexico. The entire 

 area of the Mediterranean is of course included. 



There are added, however, in the present Catalogue certain 

 Mollusca, which come from seas beyond those which are indicated in 

 the last paragraph. Inasmuch as much light is thrown upon the 

 Mediterranean by the study of the distribution of its Fauna in a 

 southerly direction, the Mollusca of the Madeiran Province have been 

 procured. Such species as are found in that Province but not in the 

 Mediterranean are indicated by the letter M placed after them. 



With a view also to a greater knowledge of the distribution of 

 the Arctic and Circumpolar Fauna, I have been glad to procure 

 Mollusca from the Arctic and North Temperate portion of the Pacific, 

 especially from Behring Strait and the Arctic coasts of Asia. The 

 few torms from this district which are not as yet recognised as 

 Circumpolar are distinguished by the appended letter P. 



The general arrangement here adopted for the Mollusca is that of 

 Dr. Paul Fischer in his recently published " Manuel de Conchy- 

 liologie." 



