34S 
CLASS III. — ORDER I. 
tracted from its ashes, which even sometimes ex- 
ceeds half the weight of the dried Polypidom. 
They differ from the marine Spongia by their fresh- 
water habitation, and by their disagreeable smell 
when first taken from the water. 
These singular beings are yet but little known ; no 
exotics are to be found among the collections. It is 
however probable that the fountains, rivulets, and 
rivers of other regions contain them as well as our 
own ; but they have not been sufficiently attractive 
hitherto to catch the attention of voyagers, occupied 
in more important objects, or engaged by forms more 
elegant, or colours of greater brilliancy. 
The Ephydatias are seldom of the same form ; 
their colour is green, of different shades, apparently va- 
rying with the nature of the body to which they adhere. 
They inhabit fresh and limpid waters, covering 
stones, roots, and almost every substance that comes 
within their reach ; frequently acquiring considerable 
size. 
CANAL. 
1. Ephydatia canalium. Branching and dicho- 
tomous ; branches round and bent. 
In an aqueduct. 
FLUVXATIC. 
2. Ephydatia jluviatilis. Upright, fragile, and of 
no particular form. 
In ponds. 
FRIABLE. 
3. Ephydatia friabilis. Ashy, friable, sessile, 
without form, and a little branching. 
In a lake near Buda. 
