ANNELIDA. 



9o 



Thied Order — Tubicolous xVnnelidans. 



The Tubicolous Annelidans, as their name imports, 

 reside in tnbes, which are either composed of a dense 

 shelly substance, or constructed by gluing together 

 fragments of sand, small stones, and other similar 

 materials. To the former section belong 



The Serpulse* (Serpulce) (Fig. 65), found on every 

 coast, encrusting stones or shells, or any substance that 

 has lain for any length of time at the bottom of the sea. 

 The animal inhabiting these shells is a worm entirely 

 destitute of limbs, but its front part, or head, during life 

 presents a very beautiful spectacle, for from each side 



Fig. 65.— sekpula. 



there spreads an elegant plume, composed of branched 

 filaments of a rich scarlet or crimson hue, which float 

 loosely in the water, and constitute the gills, or branchiae. 

 Besides these splendid branchial fringes, the head has 

 one of its tentacles expanded into a broad, triunpet -shaped 

 extremity, which accurately fits the mouth of the tube, so 

 that when the creature is alarmed, it quietly draws in this 

 singular trap-door, and remains secui*ely shut up within 

 its shelly abode. 



The Terebellae "f inhabit factitious shells, composed 



* Serpo, to twist about lilie a serpent. 

 t Terebelluin, a little auger or piercer. 



