57 
VENUS Imeolata* 
TAB. XX .— Upper Figure . 
Spec. Chau. Rather gibbous., ovato-subcordate ; 
four-fifths of the surface covered with obscure 
zigzag striae t anterior side smooth ; edge entire. 
Syn. Venus castrensis of Lion, Parkinson Org » 
Rem. 3 . p. 187, 
Length about one inch and three quarters, width about 
two inches and an half; the beak is rather prominent, and 
the thickness of the shell not remarkable; the cicatrix is 
cordate, but not well defined. 
This is the Venus from Blackdown, near Collumpfon in 
Devonshire, spoken of by Mr, Parkinson, and which I had 
much wished to see, and my wishes were soon gratified, for 
almost the same day a parcel arrived from Miss Hill, with 
this extraordinary specimen, which, notwithstanding the 
great change that has taken place in its substance which 
is now siliceous approaching to Agate or Calcedony, has 
the elegant zigzag lines yet distinct. It adheres by its inside 
to agglutinated sand so strongly, that I could not attempt to 
get at the hinge without danger of spoiling it; I therefore 
have placed with it a shell which shows the hinge, and from 
the outward contour appears to be of the same genus The 
numerous greenish black particles of Chlorite in this sand 
characterize the stratum. 
This shell does not agree with Linnaeuses description of 
Venus castrensis. 
