PEESXWICH CRAG-BEDS OF SXJFPOLK AND NOEFOLK. 131 



ever, have an equally wide range in a southern direction, and 

 the other 4 are entirely southern in their range. Owing to the way 

 in which so many Cirripedes attach themselves to floating seaweed, 

 wood, shells, Crustacea, and Bryozoa, their range is generally wide, 

 and they have less definite value in a geological point of view. Mr. 

 Darwin states that Pyrgoma anglica is found from 12 to 45 fathoms, 

 and the Verruca Stromia at all depths from low water to 90 

 fathoms. 



Corals. — M. Milne-Edwards could only recognize 3 species of 

 Corals in the Coralline Crag, and considered them all to be extinct 

 species, — one, the Cryptangia Woocl'd of the lower Crag zones, belong- 

 ing to an extinct genus. Professor Duncan, however, informs me 

 that in the last expedition of H.M. ship ' Porcupine,' specimens of 

 a Coral were found alive in Tangier Bay, which could only be re- 

 garded as a variety of the Sphenotrochus intermedius described by Von 

 Miinster. The habitat of that species is between 60 and 300 feet. 

 Professor Duncan also says that the deep-sea dredgings off the south- 

 west coast of Spain in the same expedition of the ' Porcupine ' 

 have yielded a Flahellum which, -although not very closely allied to 

 the Crag form (i^. Woodii), is found in the Miocene deposits of the 

 south of Spain. This species exists on the sea-bed at a depth of 

 from 1824 to 5964 feet, and therefore it is reasonable to assert that 

 Flahellum Woodii was a deep-sea form. It is more closely allied 

 to Indian species than to those of more northern seas, viz. Flahellum 

 laciniatum, Ed. & H., and Flahellum MacAndreivi, Ed. & H. Prof. 

 Duncan further remarks that these genera are such as chiefly inhabit 

 deep water, and that neither they nor their congeners have ever 

 formed part of the assemblage which produces reefs. 



Ecliinodermata. — 16 species have been found in the Coralline 

 Crag, of which only 3 are recent species — 2 British and Scandina- 

 vian, and 1 Mediterranean. If we were to judge by genera alone, 

 several of the Crag genera are such as are now found only in warm 

 and tropical seas. Their range of depth is variable. The Comatulce 

 generally inhabit deepish water. Diff'erent species of Echini seem 

 to mark the difi'erent zones of the Crag. 



Foraminifera. — One hundred and five species (including notable 

 varieties) have been recorded * by Messrs. Eupert Jones, W. K. 

 Parker, and H. B. Brady. Of these, 5 possibly are derived from 

 other strata ; 53 are living species, and 47 are extinct. Of the 

 recent species, 37 are stated by the authors to be living in the 

 North Atlantic and 37 in the Arctic seas. The species of the 

 Foraminifera from one bed of Crag at Sutton, they observe, " are 

 remarkable, for the most part, for size and abundance. The 

 leading forma are Miliola, Lagena, Nodosarina, Polymorphina, Tex- 

 tularia, Planorhulina, Ptdvimdina, and Nonionina. As a fauna, 

 they are best represented (in our collections) by dredgings from the 

 Atlantic, south of the Scilly Isles, at from 50 to 70 fathoms, and 

 from the Mediterranean north of Sicily at 21 fathoms. Erom all 



* "Monogr. Foram. Crag" (Pal. See), part 1, 1866; and "Monogr. Poly- 

 morphina " (Linn. Soc), 1870. 



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