70 



GEOLOGY. 



Oreasters, from the Chalk ; the fine Solaster Moretonis, from the Gerat 

 Oolite, with thirty-three arms ; and the five-rayed Stellaster Sharpii, 

 from the Northampton Ironstone, deserve special notice. (Table- 

 case 75.) 



3. The " Brittle-stars," such as Ophioderma Egertoni, from the 

 Lias of Lyme Eegis, and others, closely resemble those now found 

 living on our own coasts. 



4. The Stone-Lilies (Ckinoidea), so rare in our modern seas, were 

 once exceedingly abundant in the Secondary and Palseozoic periods. 



They were fixed during life to the sea-bottom by means of a flexible 

 stalk. The body was of variable shape, but covered by calcareous 

 plates, and surmounted by branched arms from five to ten in number. 



The most striking objects of this group are the Lily-encrinites 

 (Entrochus liliiformis), from the Muschelkalk of Brunswick (Wall- 

 case 17) ; the Pear-encrinite (Apiocrinus Parkinsonis), from the 

 Bradford Clay, of Wiltshire (Table-case 75) ; the beautiful Penta- 

 crinus Hiemeri, from the Lias of Boll, Wurtemberg, and the P. 

 briareus, from Lyme Kegis, Dorset (Wall-case 16 and Table-case 74). 



Placed on the wall, near the case of Lias Pentacrinites, is a fine 

 polished slab of " Entrochal or Encrinital marble," from Derbyshire, 

 almost entirely composed of the broken stems of Actinocrini (Stone- 

 lilies), from the Carboniferous Limestone. The cases containing the 

 older forms, from the Wenlock Limestone (U. Silurian), near Dudley, 

 are deserving of special notice ; also the fine series of N. American 

 Carboniferous and Silurian genera (Wall-cases 17 and 18). 



The curious and anomalous forms of Cystoidea and Blastoidea, 

 from the Carboniferous and Silurian rocks, are very well represented 

 here. 



7. The Holothuroidea, which have no hard test, properly so called, 

 and in which the body is vermiform, have small plates and spicules 

 scattered through the skin. Those of Synapta (shaped like micro- 

 scopic anchors) and of Chirodota (like minute wheels) have been 

 found by washing the decomposed shales of the Carboniferous Lime- 

 stone of the East of Scotland. 



Narrow Gallery No. 3. — This is retained as a "Reserve Gallery " 

 for study purposes. 



Gallery C. — This is the third of the wide Galleries, and is now 

 being rapidly fitted up with Table-cases and Wall-cases similar to 

 Galleries A and B already noticed. 



When completed this Gallery is intended to receive along its 

 Western side : — 



Division E. Cq3lesterata. 



Class 1. Actinozoa (Rayed animals). 

 ,, 2. Hydrozoa (Bydroid „ ). 

 Comprising the Fossil Corals and Hydrozoa. in which latter Class are 

 placed the Graptolites. 



