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A DECADE OF CRAG W O R K .
A DECADE OF CRAG WORK. BY
CLAUDE M O R L E Y ,
F.E.S.,
F.G.S.,
F.Z.S.
IT seems well to put upon record what our Society has accomplished by research into the innumerable Fossils of the Crag during the first ten years of its existence. The scarcity of investigators has been most disappointing, and those are now mainly dead. Consequently the results have brought forth no new species ; and even the specimens unearthed have not been as fully identified as one could desire. We know, for instance, nothing whatever about the 105 kinds of F O R A M I N I F E R A described from the Coralline or White Crag by M M . Rupert Jones, W. K. Parker and H. B. Brady, though over half these have been found in Essex at Walton-Naze alone. Of PORIFERA (Sponges), both the kinds that occur there are common in our White-crag at Sutton, Sudbourn, Gedgrave and especially numerous at Aldeburgh on the Oyster-shells of Anomia patelliformis, L. In Ramsholt cliff Pectunculus pdosus, L., at Butley priory Cyprina Islandica, L., at Bentley Station Cardium interruptum, Wd. and Venus imbricata, Sow., and at Bawdsey cliff Buccinum Dalii, Sow., have their shells bored by these Cliona celata, Gnt. and Grantia compressa, Flem. COELENTERATA OF THE CRAG.—The sole HYDROZOON, Hydractinia circumvestiens, Wd., is infrequent through abrasion and more often seen on Trophon antiquus, Müll., Murex and Pholas crispata, L., at Walton-Naze than anywhere in Suffolk, where I have noticed it at only Sutton and Gedgrave.—Milne-Edwards found three kinds of C O R A L in the White Crag and five are known in the Red, all occurring at Walton ; but Prestwich considered those in the latter merely derived from the former. In Suffolk they abound in the White and only the large Cryptangia Woodi, E-H., in the Red at Butley ; at Ramsholt it often strews the Deben fore-shore, where blocks extend to over five inches in diameter ; smaller sections occur at Sudbourn, Gedgrave and Sutton ; at Aldeburgh in January 1932 I found a cylindrical branch ten inches in length. An apparently distinct and quite smooth species occurred at Sutton in March 1936 ; and another slender one, presumably Trochocyathus Anglicus, Dune., has turned up rarely at Sudbourn, Sutton and Ramsholt. The stubby Balanophyllia calicula, Wd., is very general at Newbourn, Foxhall, Bentley, Tattingstone, &c ; but the pedicelled Flabellum Woodi, E-H., has appeared to me at only Bawdsey, Foxhall, Newbourn and in the Chillesford Bed at Chillesford Lodge in March 1932. Sphenotrochus Boytonensis, Tom., also seems rare at Sudbourn and Sutton ; though 5. intermedius, Mün., abounds at both, at Foxhall, Ramsholt and WaltonNaze.—BRYOZOA (Polyzoa as they used to be called, Zoophytes or Corallines) are confusing in their multiplicity: Prof. Busk described 95 kinds, of which eighty occur at Walton-Naze. I have