182 MARINE INVERTEBRATES 
FAMILY TEREBELLIDE 
The body is cylindrical and largest on the anterior end; there 
are one to three pairs of more or less branched gills on the an- 
terior end, and the ventral surface of the anterior segments is 
thickened by glands which secrete mu- 
cus for tube-building. These gland- 
spaces are called shields. 
Grnus Thelepsus 
T. cineinnatus. Two to four inches 
long; pale red; marked like lacework on 
the back; gills have numerous unbranched 
filaments arising separately in two trans- 
verse rows; tubes thin, transparent, flexible, 
and hung with foreign substances ; attached 
along the whole length. 
Genus Amphitrite 
A.ornata. Twelve to fifteen inches 
long; flesh-color, reddish, or brown; three 
> pairs of red plume-like gills and numerous 
Amphitrite ovnali flesh-colored tentacles around the anterior 
end; tentacles constantly in motion and 
sometimes extended eight or ten inches; tubes a quarter of an inch or 
more in diameter, and firm, be- 
ing composed of sand and mud. 
It is found under stones in mud, 
gravel, and sand at low-water 
mark from Cape Cod to New 
Jersey, often associated with 
Cirratulus grandis. 
GENERA Polycirrus, 
Chetobranchus 
P. eximius, C. sanguineus. 
These are two species of bright- 
red, fragile worms, found under 
stones, in mud. They do not 
form tubes. The first is a small 
worm, the second twelve to 
fifteen inches long. Both have 
long, crowded tentacles extend- 
ing in every direction and dis- 
tended as the blood flows into 
them. C. sanguineus has ten- Polycirrus eximius. 
