FROM THE WHITE LIAS. 67 



Avicula contorla in England, Wales, and Ireland, are not of that character in which Corals 

 would be usually found ; but the Azzarola beds of Lombardy are, as has been already 

 noticed, highly coralliferous. The Montlwaltia from the British Avicula contorta series is, 

 however, of some importance as a species, for it is the oldest Secondary form, there being 

 no Madreporaria between it and the Carboniferous fauna except the few species of the 

 Permian. 



The White Lias, which was deposited under very different conditions to the Avicula 

 contorta series, contains two genera of Corals, but the species are indeterminable, on account 

 of the specimens being either in the form of casts or so altered by a destructive mineraliza- 

 tion as only to present sections of their septa and part of the epithecal covering. 



The White Lias of Watchet contains Montlivaltia and stunted conico-cylindrical 

 TliecosmiUce. A species of this last genus has its wall and epitheca very well shown (fig. 3). 



Fig. 3. Thecosmilia, from the White Lias of Watchet. 



No Thecosmilia from the White Lias can be determined to belong to the species 

 Michelini or Martini, but there is a cast of a Coral in the White Lias of Sparkfield which 

 has some resemblance to casts of Thecosmilia Terquemi, Duncan. 



Fig. 4. Cast of a Thecosmilia, from the White Lias of Sparkfield. 



Several specimens, probably, of Montlivaltia, from the White Lias of Warwickshire, 

 are only distinguishable by the radiating septal lamince (fig. 5). 



