﻿ANALYSIS OF SYNOPTICAL LIST. 



219 



FORMATION. 



Coralline Crag; 



Walton (or Older Red) Crag 



Rest of Red Crag (except ' 

 Scrobicularia beds) 



Fluvio-marine Crag 



Cliillesford beds. 



Lower Glacial 



Middle Glacial 



Upper Glacial 



Post Glacial 



20 



13 



30 



36 



19 



13 



21 



21 



19 



154 



61 



78 



38 



44 



43 



10 



26 



51 



14 



14 



24 



10 



22 



12 



10 



23 



142 



50 



55 



14 



12 



391 



148 



199 



111 



87 

 29 

 94 



59 

 49 



REMARKS. 



Of the 24 species not known either as 

 British or Mediterranean there is but one 

 (and that a doubtful identity), Cerithi- 

 opsis lactea, which is Arctic. The re- 

 mainder inhabit seas of lower latitude 

 than Britain. See Note A. 

 Of the 10 species not British or Mediter- 

 ranean two are Arctic and the rest 

 inhabit seas of lower latitude than 

 Britain. See Note B. 

 Of the 22 species not British or Mediter- 

 ranean thirteen are Arctic, and the rest 

 inhabit seas of lower latitude than 

 Britain. See Note C. 

 Of the 12 species not British or Mediter- 

 ranean three inhabit seas of lower lati- 

 tude than Britain, and the rest are 

 Arctic. See Note D. 

 Of the 9 species not British or Mediter- 

 ranean two inhabit seas of lower latitude 

 than Britain, and the rest are Arctic. 

 See Note E. 

 The 4 species not British or Mediterranean 



are all Arctic. See Note F. 

 Of the 10 species not British or Mediter- 

 ranean three inhabit seas of lower lati- 

 tude than Britain, aud the rest are 

 Arctic. See Note G. 

 The 23 species which are neither British 

 nor Mediterranean are all Arctic. See 

 Note H. 



The 4 species which are neither British 

 nor Mediterranean are all Arctic. See 

 Note I. 



Note A. — The twenty-four species in the Coralline Crag are the following, viz. Erato mangerice, which 

 is West Indian ; Nassa granulata, which is Japanese ; Pyrula reticulata, a tropical form ; Trophon Custifer, 

 Pleurotoma hispidula, Cerithium cribrarium, Ghemnitzia varicula, Sigaretus excavatus, Bullcea venlrosa, and 

 Lasoea pumila, which are reported by Mr. Jeffreys to have occurred in the abyss of the Atlantic ; Cancellaria 

 mitreeformis, and Scalaria obtusicostata, which he reports as West Atlantic ; Trochus multigranus, Necera 

 obesa, and N.jugosa, which he reports from Atlantic and Lusitanian abysses (and the two first of which are 

 also Scandinavian) ; Scalaria subulata, which he reports from the Canaries ; Bulla conuloidea, which he 

 reports from the Lusitanian Coast ; Ccecum mammillatum and Skcenia ovata, identified by Dr. P. Carpenter 

 with Pacific shells ; Cardita scalaris, another Pacific shell ; Gastrana laminosa, a South African shell ; 

 Natica pusilla and Nucida proximo, species inhabiting the coast of the United States ; Cerithiupsis lactea, 

 which, if identical with the Crag shell, (of which I am doubtful) is the only exclusively Arctic species 

 among the twenty-five. 

 29 



