14 Mr. ellis on the Gorgonia. 
\ 
from one to another. M. du hamel, an author of the 
firft reputation, hath clearly demonftrated this in his Pby- 
fique des Arbres , vol. II. p. 119. tab. 11. /. 91. Now 
in the gorgonia , the fupport, or what is called the woody 
part, is indeed furnilhed with a kind of a pith or medulla: 
but when we cut the Item or branch through the middle 
lengthwife, we find no paffage whatfoever between the 
pith of the ftem and that of the branch, each being fur- 
rounded with a hard covering of its own, which hath no 
perforation, nor admits of any communication. Every 
branch of a gorgonia therefore hath its own pith or me- 
dulla peculiar to itfelf, which is never found palling into 
that of another, fee fig. 1 1 . a. the natural fize, b. magni- 
fied. Again, in trees, the pith is largeft in young fhoots, 
and difappears in old Items : in the gorgonia the medulla 
is of the fame diameter in the old Items as in the young 
branches. In the longitudinal fedtions of frefh fhoots of 
trees, the pith in the microfcrope looks like a number of 
jointed tubes united together; and in thecrofs fedtions, it 
appears like fo many circles. In dried lpecimens the tu- 
bular appearance in the longitudinal fedtions is more ir- 
regular ; they look rather like longitudinal ranges of little 
tranlparent blebs, and thecrofs fedtions appear like circles 
interledting one another in the margin; but there are 
many varieties of figures in the pith of different vegetables; 
what is mentioned here, is the common appearance of pith 
in molt plants. When we cut a dry branch and item of a 
gorgonia through the middle lengthwife, the pith appears 
divided into many little tranfverle membranes, like fmall 
7 white 
