CORALLINE CRAG. 459 



Belgian Crag, is not abundant in this country. Among the Fish- 

 remains (Otoliths, etc.) are Alorrhua (Cod), Merlangus, together 

 with remains of Platax Woodwardi, Rata antiqua, and Zygobatis 

 Woodiiardi. Mr. Wood considers that the Coralline Crag was 

 deposited in the sea at no depth greater than 300 feet. 



Suffolk Bone-bed. — In 1 843 the Rev. J. S. Henslow called attention 

 to the occurrence of phosphate of lime in 'pebbly beds' (nodules) 

 of the Red Crag at Felixstow ; and from the fact that some of the 

 nodules yielded upon analysis 56 per cent, of the phosphate, he was 

 led to suggest their employment in the preparation of manure for 

 agricultural purposes. These observations led to further important 

 discoveries of phosphatic nodules (see p. 410), for Mr. Henslow 

 also observed their occurrence in the 'Cambridge Greensand.'^ 

 These phosphatic nodules of the Crag have been extensively 

 worked, and being associated with many vertebrate remains, in a 

 highly mineralized condition, the layer has been termed the Suffolk 

 Bone-bed. 



This Bone-bed or ' Coprolite bed,' has been described by Prof. 

 E. Ray Lankester as being from half a foot to three feet in 

 thickness, and lying upon the London Clay in Suffolk wherever 

 the Red Crag and the Coralline Crag are found. It is composed of 

 rounded phosphatic nodules called ' coprolites,' and water-worn 

 teeth and bones of Mastodon Arrerneiisis, Rhijioccros incisivus, R. 

 ScJileiermachcri, Cervus dicranoccros, Sus, Tapiriis, Ursiis Arvernctisis, 

 Cam's Ttilpes, Hyccjiarctos, Felis pardoides, Hipparion, Hyana striata, 

 Halitheriiim Canhatni, Bdemnoziphiiis, Chonezipliius, TncJurhiis, 

 Delphinus, Cetotolites or ear-bones of Whales {Balcena, etc.); bones 

 of the Bird Diomcdca \ teeth of Sharks {Carcharodon 7Jiegalodon), etc. 

 Prof. Lankester considers that the Cetacean remains were derived 

 from the lowest Crag-deposits known in Belgium as the Diestian or 

 Black-crag. Most of the ziphioid bones bear the marks of Pholas- 

 borings." Prof. Prestwich, however, believes that the Mastodon and 

 Rhinoceros may have lived during the period of the Coralline Crag ; 

 the Whale certainly existed at that time.^ 



Among the coprolites and bones we occasionally find fragments 

 of septaria, teeth of Fishes, and Crustacea derived from the London 

 Clay, also Chalk flints (often encrusted with Barnacles), Greensand 

 chert, quartz, porphyry, etc. 



The ' coprolites' yield from 45 to 60 per cent, of phosphate of lime ; they have 

 been worked near Sutton, Boyton, Butley, Trimley, Bawdsey, Shottisham, etc. 

 The beds are however becoming exhausted. According to Prof. Prestwich seams 

 of phosphatic nodules, or dispersed nodules, maybe found through the whole of 

 the Red Crag ; and all of them were probably derived from the bed at the base 

 of the Coralline Crae. 



^ Memoir of the Rev. J. S. Henslow, by the Rev. L. Jenyns (Blomefield), 1S62, 

 p. 201 ; Q. J. i. 36 ; see also Buckland, T. G. S. (2), iii. 234. 



"^ Geol. Mag. 1868, p. 256; Q. J. xxi. 224 and xxvi. 501 ; see also Owen, 

 Q.J. xii. 217 ; Wood, Q J. xv. 32 ; J. E. Taylor, Geol. Suffolk (reprinted from 

 "White's History), 1884 ; R. Lydekker, G. Mag. 1SS4, p. 443, Q. J. xlii. 364. xliii. 



^ Q.J. xxvii. 117, 133, 326. 



