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MARINE INVERTEBRATES 



FAMILY TEEEBELLIDJE 



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. 



GENUS Thelepsus 



T. cincinnatus. 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 

 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, 

 Chcetobranchus 



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- poiyarna 



Amphitrite ornata. 



