[ x 93 ] 
compofe the branches, we find, that the knobs con- 
lift of little fponge-like tubes interwoven together, 
as they appear magnified at Fig. D ; and the ihank 
or part between the knobs is compofed of itony 
tubes, that are more eredt (See the piece magnified 
at E ) : thefe tubes appear to be branched from the 
lateral holes at FF. The Fig. E likewife fhews the 
appearance of the tubes on the furface of the main, 
item. 
The radiated openings in the little wart-like figures 
on the furface of the branches are guarded by eight 
pointed valves, as magnified at Fig. I. : thefe inclofe 
the heads of the polype, one of which is figured at K. 
The item of this fpecimen is fo intirely diverted of 
its yellow mealy covering, that we may eafily trace 
the manner in which the animals, that compofe it, 
have carried up their itony tubular cells, which lie 
fide by fide along the furface. Thefe tubes have 
itill fome marks of fponginefs at particular diftances, 
which, as they come to join together, form thofe 
irregular crofs-lines, that furround the item in feveral 
places. See Fig. A. 
In other fpecimens I have obferved the principal 
items covered over with calcarious tubes, fuch as 
I have defcribed in the Eflay on Corallines, &c± 
in that lpecies of keratophyton called Venus’s Fan. 
Plate 26. 
The fponginefs of the knobby joints occafions 
that exceifive brittlenefs in the lefier branches ; 
which accounts for the difficulty, which Rumphius 
mentions, of getting good fpecimens of this beau- 
tiful coral. 
I have lately feen a white pipy and itony coral 
Vol. 50. C c with 
