100 ZOOLOGY. 
conical and granular feet, decreasing in size from the middle of the body 
towards each end, and having short bristles at their extremity; no cirri, 
gills, nor similar appendages. The head is distinct, with two stout annulate 
antennze, and the mouth has a pair of corneous jaws. Peripatus juliformis 
of Guilding, from which the characters are taken, is three inches long, dark 
brown, annulated with yellow, the dorsal line black; and it has thirty feet 
on each side. Lacordaire found a specimen in Cayenne, sunk in the mud 
at the margin of a river, and Goudot found another species near Table 
Mountain in South Africa, under a stone in a shady place. The nervous 
system differs from that of the other annelida in being bilateral (somewhat 
as in Malacobdella) ; and on this account, Gervais is of opinion that it 
forms the type of a distinct group of worms, whilst Milne Edwards, 
who discovered this peculiarity, considers it as indicating a passage to 
Nemertes. See Kirby’s Bridgewater Treatise, p. 259, pl. 8, fig. 1, 2. 
fam. 7. Chetopteride. The genus Chetopterus was formed by Cuvier 
for a worm from the Antilles, eight or ten inches long, inhabiting a tube of 
a parchment-like consistence, whence its name Ch. pergamentacerus. 
There are neither rostrum, jaws, nor a proper head. There is a lip with 
two rudimentary antennee, followed by a disk with eight or nine pair of feet, 
succeeded on each side by a wing-like projection, bearing bristles. The 
branchize are medial, and in the form of lamine; posterior extremity with 
numerous lateral feet. } 
fam. 8. Arenicolide. In Arenicola the body is cylindrical, composed of 
a moderate number of segments subdivided by numerous wrinkles. The 
head is rudimentary, with a small terminal rostrum ; no jaws, eyes, antenne, 
nor cirri. The feet have two branches, and are armed with simple and 
armed bristles ; branchiz in bunches divided lke the branches of a tree, and 
arranged in pairs along the middle portion of the body, numbering from 
thirteen to twenty pair. They burrow in the sand about low water mark, 
and are extensively used by fishermen as a favorite bait for marine fish. 
A. piscatorum is eight or ten inches long. 
Orver 3. CrepHaLtopranouiA (or Zubzcola). These sedentary annelida 
live in calcareous, sandy, or membranaceous tubes; the soft appendages 
are generally confined to the anterior extremity; the head is indistinct, 
without eyes, rostrum, or jaws; the branchie are plumose, and situated at 
the anterior extremity (pl. 75, fig. 68). They comprise the two families 
Serpulide and Amphitritide. The former is distinguished from the latter 
by having the branchial plumes separated into two masses by a pedunculated 
operculum, or covered by a solid one when withdrawn within the shell. 
Fam.1. Serpulide. The genus Serpula (pl. 75, jig. 70) has the body 
tapering posteriorly, the mouth terminal, and surrounded with a crown of 
long, feathery, and often finely colored branchize, which give the animal the 
appearance of a zoophyte. These are used in taking the small living objects 
upon which they feed. The feet are lateral, the seven anterior pair attached 
to a membranous base. The part bearing these feet forms a kind of thorax 
distinguishable from the remaining part of the body. From the internal 
base of each of the two masses of branchize a filament arises, one of which 
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