VOL. XVI.(2) | INFERIOR-OOLITE ECHINOIDS 163 
Clypeus Ploti is very common in parts of the Mid and 
North Cotteswolds. Indeed, in places, the CZyfews-Grit 
might almost be said to be made up of this echinoid. 
The farthest point south at which it has been found is 
at Coombe Quarry, near Wotton-under-Edge, in the 
South Cotteswolds, where it has been collected by one of 
us (L.R.) In the Bath-Doulting area, Clypeus Plotz is 
replaced by Clypeus Agassizt, which occurs at about the 
same horizon. A tare variety of the latter species, CZypeus 
Agasstzi, var. conicus, var. nov., has been found by 
Mr J. W. Tutcher in the Upper Coral-Bed (Truellet) of 
Dundry Hill. 
Clypeus Agassizt is found associated with Clypeus altus 
around Castle Cary, Bruton, and Crewkerne.’ Towards 
the south, it appears to give place entirely to C4ypews altus. 
The furthest point north at which CZypeus Agasszzi has 
been found is Stinchcombe Hill, where it occurs in 
the local CZypeus-Grit. 
VI.—REMARKS ON THE SPECIES, PRINCIPALLY WITH 
REGARD TO THE HORIZONS AT WHICH THEY 
OCCUR. 
(1) Observations on known species. 
In the case of certain species dealt with in the follow- 
ing pages, it has been found that depressed and conical 
forms of a species occur, which differ only in the matter 
of height. 
Some of the forms have been separated by former 
writers as distinct species. Since, however, they occur 
at the same horizon, and in most cases a transitional series 
can be traced from the one into the other, they have been 
regarded as varieties in the present paper. 
r Mem. Geol. Surv., vol. iv. (1894), pp. 71 and 86. 
