PLATE XVIII. 



Class POLYZOA. 



Bugula. 



Fie. 1. DIAGRAM OF A POLYZOON. (After Busk.) 



t. tentacles : 1. lophophore : m. mouth : o. oesophagus : s. stomach 

 i. intestine : a. anus : g. nerve ganglion : /. funiculus. 



FIG. 2. BUGULA PLUMOSA. x 1. 



FIG. 3. ZOGECIA OF BUGULA: FRONT VIEW, x 10. 

 z. zocecium : a. the avicularium. 



FIG. 4 ZOCECIA OF BUGULA: BACK VIEW, x 10. 

 FIG. 5. THE AVICULARIUM. x 50. 



-, 

 Menibranipora. 



FIG. 6. ZOCECIA OF Mcmbranipora menibranacea. x 1. 

 FIG. 7. THE SAME, x 25. 



Class BRACHIOPODA. 



Lingula. 

 FIG. 8. LINGULA. x 1. 



FIG. 9. LINGULA : VIEW AFTER REMOVING THE VENTRAL VALVE AND PART OF 

 THE MOUTH, x 1. 



c. capsule of the pedicle : p. a. posterior adductor muscle : p. posterior 

 adjuster muscles : a. anterior retractor muscle : I. liver : 

 c. a. central adjuster muscles. 



