J. D. Dana on Zoophytes. 67 
animals. The word zoophyte,* originally used by Linnzus, 
alluded to their supposed intermediate nature. Still, the name is 
sufficiently appropriate, although the idea in which it originated 
is exploded. They are plants in form even to the coral-polyps 
which blossom over the surface. Yet in the mode of receiving, 
digesting, and assimilating nutriment, and every other function 
of life, they are animal. 
The relation of the coral to the coral animal, and the mode of 
its formation, are subjects about which much error has been pub- 
lished ; and although now correctly explained in some scientific 
treatises, very erroneous impressions largely prevail. Without 
entering into particulars in this place, one single fact should be 
here stated and duly considered. It is this:—coral is not the 
residence or hive of polyps. On the contrary, it is contained 
within the polyps, instead of containing them. It is formed 
within them by animal secretion, as bones are formed within 
other animals; and in most living zoophytes it is wholly en- 
closed, showing not a spine or point externally. ‘This is the case 
with the Madrepore ; no part of the coral is seen externally while 
the animal is alive in the water. The idea that coral polyps 
retreat into cells, is therefore wholly without foundation. Some- 
times the summit or flower-shaped part of the polyp becomes 
concealed, in a manner a little similar to the withdrawal of a tur- 
tle's head; but even this semblance of retreat is by no means 
general among the ordinary coral zoophytes. 
here is no mechanical accumulation of material by the polyp. 
They are as unconscious of the coral secretions going on within 
them, and as free from actual labor and industry, as we are in 
the construction of our bones. 
IL 
a‘ The word zoophyte is fr heG k Zwo animal, and Que, te 
Blainville States that the term was introduced by Sextus Empiricus and Isodore de 
Seville in the sixth century. It has been differently restricted in its use by au- 
single polyp, or phytozoa to polyps in general. These cannot supply the place of 
the very convenient terms zoophyte and zoophytes. Moreover the term phytozoa 
or phytozoaires (plant-animals) has been applied to the minute monad-like cellules 
mae the tissues of some plants, and supposed to be animalcules or plant- 
en é 
