90' PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [BcC. 6, . 



from the Lower Lias, and there still remains a great gap in our know- , 

 ledge of theMadreporaria, between the Permian and the Liassic strata 

 yielding Isastrcea Murchisoni, Wright, and Thecocyathus Moorei, 

 Ed. & H. 



Lately, large series of Middle and Lower Liassic corals have passed 

 through my hands, and MM. Chapuis and Dewalque in Eelgium, De 

 Fromentel in Prance, and Stoppani in Italy have described species 

 which have enabled me to mark out the characteristic species in our 

 Middle and Lower Lias. The species from the Sutton Stone have 

 nothing in common with any species, from the Liassic strata. 

 . The White Lias of Somerset has yielded two species of Corals*. 

 Unfortunately the condition of these fossils prevents their specific 

 determination ; but they belong to the genus Montlivaltia. One is a 

 broad flat form, and is probably allied to the Montlivaltice of the 

 Lower Lias, which are usually more or less discoid. The other spe- 

 cimen is a small tall and conical form, with well-marked transverse 

 ridges on its epitheca. This peculiarity is to a certain extent Liassic ; 

 but the stunted growth and the apparently multiseptate arrange- 

 ment ally the form to the Triassic Montlivaltice. Neither of the 

 White-Lias forms are contained in the collection from the base of the 

 Sutton Stone. A Montlivaltia was discovered in the Avicula-contorta 

 series at Beer Crowcombe, by Mr. Chas. Moore f. 



In the late researches of Eeuss upon the Madreporaria of the 

 Kossen strata, numerous species were determined ; some ascend into 

 the Lias, according to Stoppani ; and all have a good Secondary facies, 

 there being no traces of Palaeozoic genera. 



The corals of the Dachstein series are still in a very unsatisfactory 

 state, as regards their description ; but it will suffice to assert that 

 they are not of the Palaeozoic genera LitJiodendron and Cyatliopliyl- 

 lum ; on the contrary, the species belong to the genera which domi- 

 nated during the Jurassic epoch. 



_ It is now tolerably evident that aU the St. Cassian corals formerly 

 associated with Palaeozoic generic names are Mesozoic forms, and 

 that only two new species, carefully determined by Reuss, belong 

 to as many genera, one being Palaeozoic, and the other closely allied 

 to a Palaeozoic genus. 



[Recently Gustav Laube i^ has concluded the examination of 

 Miinster and Klipstein's St. Cassian Sponges, Corals, Crinoids, and 

 Echinoderms: he has not distinguished a single Palaeozoic genus 

 amongst the Corals, but he has determined the great distinction be- 

 tween the Liassic and Triassic coral faunae. 



It is the defective information respecting the corals of the Dachstein 

 series, and of the relation of the St. Cassian corals to those of the 

 Dachstein and of the Kossen strata, which causes me to make a re- 

 servation in my opinion about the age of the Sutton- Stone species. In 

 other words, there is insufficient information concerning the vertical 

 range of the St. Cassian species of Corals ; and the discovery of some of 



■* Boyd Dawkins, Quart. Journ. Greol. Soc. vol. xx. j). 406. 

 , t Quart. Journ. Geol. Soc. vol. xvii. p. 511. 



J Die Faune der Schichten von St. Cassian, 1. Abtheil. 



