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kinds. On Cardiaster fossarius Dr. Wright remarks that it has 
long been a leading fossil Urchin in the U. G. S. of Wilts and 
appears to be special to that English formation. (1870, p. 297.) 
On Echinoconus castanea that it is ‘“‘ very rare”: on Holaster 
obliquus that the only known specimen came from Chute farm: 
on Caratomus rostratus that it is “found only in the U. G. S. of 
Warminster,” all which observations tend to the importance of our 
local geology. 
In the Lower Greensand of Faringdon we have two large 
Urchins (Cidaris Far. and Trematopygus Davidsoni) and half a 
dozen small species,—one Peltastes ; one Goniopygus and 4 
Pseudodiademas. They are all rare, except the Peltastes which 
occurs very abundantly as you may judge by the 100 specimens 
before you. The spines of the only Faringdon Cidaris are the 
commonest of all the fossil remains in the Coxwell pits, but a 
complete test has not yet been found. The Trematopygus is 
confined to a dark bed of sands younger than the orthodox 
‘Sponge Graveis,” and is exceedingly difficult to extract in fair 
condition on account of incrustations of oxide of iron. The 
specimens from which Dr. Wright drew up his description of the 
Trematopygus were furnished him by myself in 1874, and he has 
honoured me with an acknowledgment in the vol. of the 
Palzontographical for 1875, page 254. 
Note ON DicerAs, PAGE 416, 
According to Mr. Jukes-Browne this rare and curious fossil is not a 
Cephalopod, but a bivalve shell closely allied to the modern genus Chama. 
