130 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. 



to the Coralline Crag. Of the species and genera of Bryozoa inha- 

 biting shallow water, there is a marked absence. 



The Bryozoa make their appearance in the lowest bed of the 

 Coralline Crag. I found species of Gellepora and Escliara amongst 

 phosphatic nodules at the base of this deposit. At Ramsholt the 

 Cupula7^ia denticulata, C. canariensis, and other species were met 

 with. In ascending order they become gradually more numerous, 

 and in zone " e" they attain a large development and, further, 

 occur in the position and place of growth. The species seem some- 

 what gregarious. At Sutton we find chiefly species of Cellepora and 

 Escliara in this bed, whilst at Broom Hill little else is found but the 

 various species of Fascicularia and Alveolaria and some Cellepora. 

 In the highest bed, "/," of this division, where extremely fine sedi- 

 mentary seams are intercalated with a mass of comminuted shells, 

 the delicate Salicornaria sinuosa seems to have flourished. 



The upper division of the Coralline Crag, as is well known, is 

 composed to a great extent of fragments of Bryozoa and com- 

 minuted shells, with a certain number of entire Alveolarice and Fas- 

 cicularice and shells. As the structure of these beds shows them to 

 have been subjected to the action of shifting currents and frequent 

 reconstruction, it is probable that these banks of Bryozoan remains 

 and dead shells were formed in gTeat part by the scour of deep- 

 sea currents out of the upper beds of the lower division of the Coral- 

 line Crag. At the same time, the perfect state of the Alveolarice and 

 Fascicularice and the known habits of most of the Bryozoa render it 

 perfectly possible that many of the individuals may have lived among 

 these shifting currents and shell-banks. 



Crustacea. — Besides the specimen referred to Gonoplax angulata, 

 Mr. Woodward has ascertaiued the existence in the Coralline Crag 

 of the following species : — Cancer payurus, Carcinus mcenas, Maia 

 squinado, and Portunus puher and depurator. 



Fntomostrrtca. — Mr. Rupert Jones describes 18 species of Ento- 

 mostraca from the Coralline Crag*, 3 only of which are known for 

 certain as living forms (Cythere punctata, C. ceratopora, and Loxo- 

 concha tamarindus), all in the Atlantic — though Cythere laqueata, C. 

 suhlacunosa, C. tracliypora, and C. retifastigata have almost undistin- 

 guishable allies in the Norwegian sea ; and the subdeltoidal Bairdia 

 of the Crag has its closest analogue (B.fusca, Brady) in the Austra- 

 lian seas. The last-mentioned seems to be of deep-water habits ; 

 but the others are mostly littoral. 



As we do not know the exact distribution of the Entomostraca in 

 the Coralline Crag, we cannot speak of them in relation to the dif- 

 ferent zones. 



Cirripedes. — Mr. Darwin has described 10 species in the Coralline 

 Crag, 4 of which are from Eamsholt and 6 from Sutton. The pro- 

 portion of recent to extinct species is 6 to 4. Of these six, four are 

 species still living in the British seas, one ranging to the Scandi- 

 navian coast and one to the Arctic seas. Both these species, how- 



* These conclusions are drawn from Prof. Eupert Jones's revision of these 

 Tertiary Entomostraca in 1870 (GeoL Mag. vol. vii. pp. 155-169). 



