[ *®s ] 
Defcription of the Madrepora. 
See Tab. III. Fig. A. 
This is intirely like the coral, as to its hardnefs, 
which is equal to bone or marble. Its colour is 
white, when polifhed. Its furface is lightly wrinkled, 
and the wrinkles run lengthwife of the branches. Its 
infide is of a particular organization j having in the 
center a fort of cylinder, (Fig. D. /,) which is often 
pierced thro’ its whole length by two or three holes. 
From this cylinder are detached about 17 lamina > 
(Fig. D. k y k t ) which run to the circumference in 
ftrait lines (Fig. D. m, m, m, m,). 
Thele l a ml net are tranfverfely interfered by other 
lamina , (Fig. D. y, y,) which form many irregular 
cavities throughout the whole plant. The branches 
(Fig. A . o', g,) are conical ; and the balls of the cone 
is formed by the fummit of the branch (Fig. A. e> ej. 
Every one of thefe fummits has wrinkles on its out- 
fide, which run in the longitudinal direction of the 
branches (Fig. B. c, cjj and each wrinkle anfwers 
to a lamina , (Fig. C. e, u, e, u,) and each lamina is 
of the fhape of a prifm, (Fig. E.) the bafis of which 
is warty, and faces the outiide, (Fig. C. e , &r,) and 
its point is cut into teeth, (Fig. E. n y n y n,) and be- 
longs to the infide. The cellule, (Fig. B. a , a y a, 
c, c, Fig. C. c, e , z/, uj which is of the fhape of a 
chalice, is compofed of thefe lamina ranged into a 
circle. 
In every one of thefe cellules is found a little pply~ 
pus , reprefented in Fig. E. but conliderably magni- 
fied 5 the mechanifm of which is this : 
O 
Three 
