AMPHITRITE. 915 
grey or lead colour. Sometimes the colours are very vivid. Green is 
always exhibited ; the fluid wherein a specimen dies is tinged with green. 
The same peculiarity follows the decay of another species, wherein green 
appears, while the subject remains entire. 
The organic structure of the Amphitrite is dependent entirely on its 
dimensions. Additional parts unfold incessantly with its advancing age ; 
nor can I conjecture where their multiplication ceases. Thus the num- 
ber of segments assigned to the body of not only this animal, but, in as 
far as I know, to all its kindred Annelides, must be qualified by taking 
the age, that is the dimensions of the specimen, into account. 
A month after a small specimen had been obtained, it did not ex- 
ceed three lines in length ; and, in another month, the plume consisted 
of seven branchial feathers. A second specimen, somewhat larger, had 
fourteen ; a third, twenty-one ; a fourth, thirty-three ; a fifth, fifty, and 
so on, up to ninety-two, the greatest profusion enumerated in this splen- 
did organic ornament—one utterly inimitable by art. 
As the ribs of the branchiz extend, the cilia multiply proportionally ; 
and while these new evolutions are advancing above, additional segments 
are forming below. Thus the energy of Nature seems never to repose, 
provided animation admits its demonstration by augmenting accessions. 
In a previous publication on the Zoophytes, I had an opportunity 
of claiming the notice of the contemplative to the formation and incre- 
dible multitude of parts belonging to the Pennatula mirabilis or Virgu- 
laria, over which that singular creature would apparently exercise a cer- 
tain controul ; yet, in as far as simple observation could appreciate, its 
power was not directed to the execution of any definite external func- 
tions. Here it is otherwise. We have before us a being still more ad- 
mirable, inasmuch as availing itself of its formation, it can discharge 
real mechanical operations, by the aid of the various organs with which 
it is provided, while several different offices have to be fulfilled. 
We are enabled to witness both the means and the end. 
It is known that all the parts of the human frame susceptible of volun- 
tary direction to a specific purpose, are limited within hundreds. In this 
humble tenant of the deep, they amount to many thousands. Its organs, 
