28 
CLASS ANNELIDA. 
dies, like two wings. The gills, in the form of laminae, are 
attached, rather below than above, and predominate along 
the middle of the body. 
There is one species, Chc&topterus Pergamentaceus , eight 
or ten inches long, which inhabits a tube of the substance of 
parchment. It belongs to the sea of the Antilles. 
THIRD ORDER OF THE ANNELIDA. 
THE ABRANCHIA, 
Have no organ of respiration externally apparent, and seem 
to respire, some like the lumbrici, by the entire surface of their 
skin ; others, like the Hirudines, by interior cavities. They 
have a closed circulating system, most generally filled with 
red blood, and a knotted nervous cord, like all the Annelida. 
There are some which still have setce, or bristles serving for 
locomotion, and others which are destitute of them, which 
gives rise to the establishment of two families. 
The first family, that of 
SeTJGEROUS AbRANCHIA, or PROVIDED WITH SET.E, 
comprehends the Lumbrici and the Naides of Linnaeus. 
Lumbricus, L., — vulgo, earth-worms — characterized by a 
long cylindrical body, divided by wrinkles into a great num- 
ber of rings, and by a mouth without teeth, necessarily re- 
quired subdivision. 
Lumbricus, Cuv . (proper), 
Are destitute of eyes, of tentacula, of gills, and of cirrhi; a 
tubercle, or sensible enlargement, particularly at the season of 
reproduction, seems to attach them to each other in inter- 
course. In their interior there is a strait rugose intestine, 
