ANNELIDA OR ANNULATA 



103 



Moufh 



—Peristomlal cirrus 



taria lack both jaws and a protrusible pharynx. They have small 



uncini, or hooked setae, and a few hair setae. Some species form 



calcareous tubes (Serpula), while others use the material available, 



furnishing a cement by which they bind together sand, shells, or 



sea weed into protective 



coverings. The Spion- 



idae include a number 



of small burrowing 



worms with long peris- 



tomial cirri curving over 



the back, and with the 



dorsal cirri serving as 



gills. The proboscis 



lacks jaws. The Chae- 



topteridae include fifteen 



species of short, stout 



worms, which live in 



parchment-like tubes. 



Wino , a porapodium 



Fig. 41. Diopatra cuprea. 

 (From Verrill.) 



Fig. 42. Chaetopterus pergamentaceus. (Original 

 drawing by H. Lammers.) 



Certain species are highly phosphorescent. Important studies in 

 Experimental Embryology have been made with the Woods Hole 

 species, C. pergaynentaceus. (Fig. 42.) In the Tej'ebellidae we find 

 a cylindrical body, having many similar lobes, and with well-de- 



