I04 



ANNELIDA OR ANNULATA 



veloped mucus-forming glands. Amphitrite (Fig. 43) reaches a 

 length of fifteen inches, and is reddish brown in color. It is found 

 in sand and mud at low water mark. Polycirrus (the blood worm) 

 is a long, slender, blood-red worm which does not form a tube, and 

 has no branching gills. The Amphictenidae are small worms which 

 form portable tubes of sand open at both ends. Cistenides {Pec- 

 tinarid) gouldii is a flesh-colored form found in shallow water from 



North Carolina northward. 

 The Cirratididae are worms 

 with a cylindrical body, having 

 many similar segments with 

 long filamentous cirri. They 

 live in burrows. 



Maldanidae form sand 

 tubes. They lack gills. Cly- 

 menella is one of the commonest 

 types. The Arenicolidae are 

 represented by but two com- 

 mon species. Arenicola mar- 

 ina^ called the " lug-worm," 

 reaches a length of ten inches. 

 It has twelve pairs of branched 

 red gills on the central seg- 

 ments. It burrows as much as 

 two feet into the sand, but can 

 be located by castings at the 

 entrance. The Sabellidae in- 

 clude a number of genera. 

 The tentacles are rudimentary, 

 the palps very large. A proboscis is present. They form mem- 

 branous tubes in mud and sand. Example — Sabella jnicrophthalma. 

 Serpulidae form long contorted calcareous tubes which are found 

 incrusting shells. {Serpula or Hydroides^ 



Older 2. Oligochaeta. — These hermaphroditic annelids lack 

 tentacles and parapodia, and have only a few setae, projecting from 

 pits in the body wall. Certain oligochaetes have external gills 

 {Nais). The head is not distinct, but has a small projection, the 

 prostomiujn, and ^ peristomiuniy which contains the mouth, but lacks 

 setae. Paired ovaries and testes are present in each animal, and 

 seminal receptacles store the sperm prior to the extrusion of eggs 



Fic. 43. 



Tufted worm {Amphitrite ornatd). 

 (Drawn by V^errill.) 



