OF THE ODONTOPHORE IN CERTAIN MOLLUSCA. 491 
ig. 29. Longitudinal ventral muscles, v/s, cut, radula and adherent infraradular sheet 
laid back, showing cartilages, ¢; cpr, downward prolongation from circular 
protractor of lips. 
ig. 30. Ventral transverse fibres of cartilages (vt/) cut open, showing dim’, the deepest 
set of longitudinal dorsal muscles; c’, backward prolongation of the 
cartilages. 
ig. 31. Cartilages completely cut apart, showing dorsal and ventral transverse fibres. 
ig. 32. Left side of apparatus in situ; letters as in figs. 26-28. 
ig. 33. Superficial muscles of left side cut away, showing left of framework ; 7rs, line 
of attachment of radula and infraradular sheet to side of mouth, deeper 
ventrally ; apex therefore rocks forward and upward at irs. 
ig. 34. Left cartilage completely removed, and median section completed. 
ig. 35. Lateral vertical section of anterior portion of Molluscan odontophore, 
diagrammatic. 
EXPLANATION OF THE COLouRs. 
CanbilacesMermmrnmen PENI vsurs) sis) a so tes) » aoeblue: 
Infra-radular sheet, with its dorsal and ventral muscles. . Red. 
RAC UM le fp al sy an bye Ape, 8)” Mellow: 
