PEEFACE. 



It has been a constant source of difficulty for many years 

 past to ascertain what work has been done by our predecessors 

 relating either to a special genus or to some faunal district ; 

 with the idea of rendering some assistance to students, the 

 present work has been undertaken. With a view to furnish- 

 ing an index to the periodical now dealt with, the few species 

 described in its pages which do not belong to the Mollusca 

 have been included ; in future work, however, — and it is 

 hoped, if sufficient support be forthcoming, to deal with 

 other periodicals such as the 'Zeitschrift fiir Malakozoologie', 

 ' Annals and Magazine of Natural History ', &c. — no forms 

 will be included which are not, in the strictest sense. Molluscs. 



The general arrangement is that of the 'Zoological Record', 

 and for those not familiar with its pages it may be noted 

 that such an entry as 'Macha wilsonii, China; Teyon, vi, p. 23, 

 fig. : n. sp.', implies that Tryon described a new species under 

 this name from China in volume vi, at page 23, and that the 

 species was figured. The sign f is prefixed to fossil forms. 



