522 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



however, and the Gasteropoda especially, have attached themselves 

 to the honeycombed or ragged edges of the bed, or have passed down 

 and are found united to the sides of any veins or fissures in the Car- 

 boniferous limestone itself. The organic remains are very varied, and 

 when the above is the case are often in the most beautiful condition. 



The peculiar character of the deposit, and the fact that few if any 

 of its organisms had previously been found in any stratified beds in 

 this country, rendered it exceedingly difficult to arrive at a satis- 

 factory determination of its precise age, though the presence of one 

 or two somewhat imperfect specimens of Gryphcea incurva at once 

 pointed it out as belonging to the horizon of that shell. By an exa- 

 mination of some of the smaller genera and species, however, a partial 

 key to their recognition was obtained, some of them being found 

 identical with those in the Liassic deposit at the bottom of the 

 Charter House Lead-mine, and with others in the Sutton Stone, and, 

 again, with species in the Lias of Bridgend and Bath. 



A close examination of the weathered surfaces of the Brocastle 

 deposit shows that it is to some extent composed of sponges, their 

 spicules being readily detected. Of this family there are at least two 

 genera, some of the spicules we have been able to detach showing 

 them to be triradiate and calcareous and allied to the recent Gran- 

 tia of Fleming. 



Foraminifera are exceedingly rare : a single specimen of Involu- 

 tina Uassica, Jones, and a Planularia are all yet seen. 



The Zoophj^ta have afforded a most remarkable harvest. A few 

 years ago, on the publication of the Monograph on Oolitic and Liassic 

 Corals by MM. Milne-Edwards and Jules Haime, I possessed two 

 out of three of the then known corals of the Lias ; and it has been 

 meanwhile considered quite fortunate to have increased that number 

 by some six or eight species. From this single locahty I have 

 been able to furnish Dr. Duncan, in whose hands they are placed by 

 the Palseontographical Society for description, with not less than 

 thirty-one species; and to these many will be added from other 

 localities. 



The Echinodermata, which appear to have been abundant, are 

 chiefly represented by dismembered joints of Pentacrinites and by 

 detached spines and plates of Echini. Of the latter there are two 

 or three genera, and part of the test of what appears to be a Ciclaris 

 Edwardsii, the same species being present in the Charter House 

 Mine. 



The Articulata at Brocastle are species of Serpulce, which are 

 common. Although I have hitherto been unable to detect Cirri- 

 pedia, this family, which is now recorded for the first time from the 

 English Lias, is common at Langan, and at Ewenney, close to Bro- 

 castle ; and the same species is found at Charter House and in the 

 equivalent of the Sutton Stone at Shepton-Mallet — though from the 

 latter place I have but one example. 



The Crustacea are to this time entirely confined to Entomostraca, 

 for the notes on which I am indebted to Professor Rupert Jones, 

 F.G.S. In the whole, six species are present at Brocastle, two of 



