58 THE PROBLEMS OF THE DEEP SEA u 



Dr. Thomson as " elegant vases or cups, with 

 branching root-like bases, or groups of regularly 

 or irregularly spreading tubes delicately fretted 

 on the surface with an impressed network like 

 the finest lace " ; and he adds, " When we com- 

 pare such recent forms as Aphrocallistes, Iphiteon, 

 Holtenia, and AsJeonema, with certain series of the 

 chalk Ventriculites, there cannot be the slightest 

 doubt that they belong to the same family in 

 some cases to very nearly allied genera." l 



Professor Duncan finds " several corals from the 

 coast of Portugal more nearly allied to chalk forms 

 than to any others." 



The Stalked Crinoids or Feather Stars, so 

 abundant in ancient times, are now exclusively 

 confined to the deep sea, and the late explorations 

 have yielded forms of old affinity, the existence 

 of which has hitherto been unsuspected. The 

 general character of the group of star fishes 

 imbedded in the white chalk is almost the same 

 as in the modern Fauna of the deep Atlantic. 

 The sea urchins of the deep sea, while none of 

 them are specifically identical with any chalk 

 form, belong to the same general groups, and 

 some closely approach extinct cretaceous genera. 



Taking these facts in conjunction with the 



positive evidence of the existence, during the 



Cretaceous epoch, of a deep ocean where now lies 



the dry land of central and southern Europe, 



1 The Depths of the Sea, p. 484. 



