[ 8 S5 ] 
I have very lately obferved a lingular kind of flat 
Balanus, on a white Mandrepora coral from the coaft 
of Italy, in the pofleffion of Mr. Mendez D’Acofta, 
F.R.S. whofe bafe appears funk into the coral, and 
of the form of an inverted cone, bending a little to 
one fide. The inward furface of this conical bafe 
fliell appears curioufly ftriated with tubular radii 
which terminate on the furface of the coral, to re- 
ceive the extremities of the fix valves, that compofe 
the upper fhell. This peculiar form of the bale 
feems owing to the animals of the coral and of the 
Barnacle growing up together, the latter keeping 
polleflion of its proper fpace, while the former cr re w 
clofe about it. 
The bottom fhell of the Barnacle like a Limpet, 
at Fig. \ 8. increafes from a fmall point by many 
thin Iheily margins, which exadly correfpond to the 
indentations which we obferve on the bafe of the 
outward Ihell ; fo that it appears not unlike the 
drawing of a fortification in miniature. 
I am, 
Dear Sir, 
Your moft affectionate Friend, 
John Ellis. 
P. S. The Rev. Mr. William Borlafe is now of 
opinion, that the Cornilh Barnacle at Fig. 1 
which he has deferibed in his Hilfory of Corn- 
wall, is rather a Limpet or Patella. 
CXIV. 
