656 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [NoV. 14, 



three Foxes would keep near the edge of a hole of water and kill the 

 Looms ; they would then carry them up a few hundred yards on the 

 land, where they were relieved by other Foxes, who carried them 

 up some distance, and then deposited them, for others to carry them 

 to some place in the cliff; but we could never manage to find out 

 their storehouse. 



7. Ou the Mollusca procured during the ' Lightning ' and 

 'Porcupine' Expeditions, 1868-70. (Part V.') By J. 

 GwYN Jeffreys, LL.D., F.R.S., F.Z.S. 



[E«ceiTed November 1, 1882.] 



(Plates XLIX., L) 



Since the publication of the last part of this memoir I have, through 

 the kindness of several eminent palaeontologists in Italy, had an op- 

 portunity of examining their rich collections of Subapennine and 

 Sicilian Tertiary shells, and of carefully comparing them with their 

 living analogues. This kind of study is indispensable to all zoolo- 

 gists in every department ; and it teaches us at least two important 

 facts, viz., 1st, the exact concordance in the most minute particulars 

 of so many species in their fossil and recent state, notwithstanding 

 the lapse of the enormous and incalculable time which has inter- 

 vened ; and 2nd, the extensive changes which have taken place 

 during the same period between the depth of the ocean and the 

 height of land in the North-Atlantic area. The latter fact has 

 been demonstrated in a short paper which I contributed to the 

 Geological Society in 1880, "On the Occurrence of Marine Shells 

 of existing Species at different heights above the present Level of 

 the Sea," and which has reference to the present work. 



The Expedition made this summer in the French vessel 'Le 

 Travailleur ' for exploring the depths of the Lusitanian seas for a 

 third time, as well as of the seas lying between Cadiz, the Canaries, 

 Madeira, and the Azores, has been most successful and productive ; 

 and I have been indebted to the obliging favour of my friend Dr. 

 Paul Fischer, for the opportunity of examining the interesting 

 Mollusca which were thus procured. The complete investigation of 

 the Mollusca in even this comparatively limited area must be in- 

 exhaustible. What shall we say then to the investigation of all the 

 various and hitherto unknown fauna which inhabit the depths of 

 every ocean throughout the whole world ! 



I will now continue my account of the Mollusca from the 

 • Lightning ' and ' Porcupine ' Expeditions. 



. Class SOLENOCONCHIA. 

 Family DENTAHiDiE. 

 1 1. Dentalium dentalis, Linne. 



D. dentalis, L.S.N, p. 1263; G. B, Sowerby, Thes. Conch, 

 pi. ccxxiv. f. 24, 27. 



1 For Part I. see P. Z. S. 1878, p. 393 ; for Part II. see P. Z. S. 1879, p. 553; 

 for Part III. see P. Z. S. 1881, p. 693 ; and for Part IV. see P. Z. S. 1881, p. 922. 



