Broivn — Arctic Deposits, Fifeshire. 509 



3rd, those of Aberdeen, to wliicli Mr. Jamieson has devoted his 

 attention. These indicate an increasing degree of cold which reaches 

 its climax in the next stage. 



5. The Arctic Shell-clay. — This is a fine clay in which the following 

 shells have been found. The names are given on the authority of 

 Dr. Otto ToreU. 



Buccinum cyaneum. 

 Natica grosnlandica. 

 Tttrritella erosa {polaris), 

 I'ecten granlandicus. 



C. nigra. 

 G. Icevigata. 

 Leda truncata. 

 L. minuta. 



Yoldia hyperborea. 

 T., nov. sp. 

 Astarte compressa. 

 Nucula itiflata. 

 Dacrydiuni vitreum. 

 Thracia myopsis. 

 T., nov. sp. 

 Tellina proxima. 

 Saxicava rugosa. 



Not only are all these species now found in arctic seas, but the size 

 of those species which have a wider distribution southwards corres- 

 ponds with the specimens of them now living in the seas of Greenland 

 and Spitzbergen. The Clay bed is more than forty feet above high- 

 water-mark ; the shells are evidently in the Clay in which they lived ; 

 and as they are all deep-water species, the level of the land must 

 have been at least 150 or 200 feet lower than it is now. 



6. The Boulder-clay. — This well-known deposit, both at Errol and 

 Elie, is beneath the Arctic Shell-clay; but, from an examination of their 

 relations, the author believes that, as a whole, they were deposited 

 simultaneously, and that the fossils enumerated represent the life of 

 the Boulder-clay period. 



The author considers that these Fife deposits may form the 

 starting point for a more rigorous classification of the superficial 

 beds throughout Scotland. W. 0. 



n. — On a New Cephalaspid. By E. Eay Lankestee, 

 Christ Church, Oxford. 



[British Association for the Advancement op Science. Dundee, 

 Section C. Geology.] 



ME. Lankester exhibited a diagram of the head of a Cephalaspid, 

 fragments of which had been described by Agassiz as Plectrodus 

 pustuliferus. It was remarkable for its long cornua, minute pustular 

 ornamentation, and the dentation of its outer margin. It was pro- 

 bably an Auchenaspis, but the posterior ' neck-plates ' were deficient. 

 Specimens of the head had been obtained by Mr. Lightbody of Ludlow 

 and Dr. Grindrod of Malvern. Mr. Lankester exhibited a diagram of 

 a restored Ce2)halapis, and noticed the existence of a series of scales 

 forming the broad ventral surface of the body and tail of this genus 

 of fishes. He also noticed the thickening of the margin of the head- 

 shield and the ornamentation of a part of its under surface, showing 

 that this particular part of the concave surface was superficial like 

 the whole of the convex surface, and not covered in by a lower jaw 

 or other plates. 



