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trading it happens to touch fome other branch, and 
then that other immediately contrails with it. When 
the main ftem, which bears the whole duller con- 
trails itfdf, then all the branches of the duller con- 
trail together alfo 5 and the whole becomes entirely 
clofed. A moment after, the branches and the 
ftem again extend themfelvcs, and the whole clufter 
thereby recovers its ordinary figure. But when the 
clufter is confiderabiy advanced, the ftem then ceafes 
to contrail itfdf any more. 
I fhall now attempt to deferibe the manner in 
which this clufter forms itfdf. 
A fingle ‘Polypus detaching from the clufter, 
fwims about in the water till it meets with fome 
proper body to fix itfelf upon. It then has a pedi- 
cle but which is not longer than the Polypus itfelf 
In the fpace of 24, hours this ftem becomes 8 or 9 
times as long as it was at the firft : and it is this pe- 
dicle which is to become the main ftem of the new 
clufter. About a day after the Polypus has been 
thus fixed, it divides itfelf into two. Ten or twelve 
hours after, thefe two Polypi again divide them- 
felves each into two more : they foon after put out 
branches, and thus retire to a greater diftance from 
each other. It is now necefiary to take notice, 
that when two of thefe Polypi are thus formed by 
the divifion of one, the one is ordinarily much 
larger than the other : this larger one remains at the 
extremity of the branch where it was, but which 
branch lengthens it feif more, whilft the other puts 
out a new branch which feems to proceed from 
the firft. The larger of thefe Polypi again di- 
vides it felf generally before the other 3 and all I 
have 
