PLATE III. 



FiiiS. 13-15. Pliildbrya limoides. 



FIG. 13. Diagram of anatomy. 



a.r.p., Anterior retractor pedis ; au.c., auricular communication; by.p., byssal papilla; 

 c.e., cephalic eye; g.o., genital orifice ; I.e., labial caecum ; p.c. pericardium ; p.r.p., posterior 

 retractor pedis ; r., renal organ ; r.o., renal orifice ; r.pc.d., reno-pericardial duct. 

 FIG. l-i. Diagram of mantle-cavity and sub-branchial ridge. 



ep.r., Sub-branchial ridge of modified epithelium ; g.tl., genital duct ; m.c., extension of 

 mantle-cavity above gill-attachment ; ov., ovum. 

 FIG. 15. Cephalic eye. 



FIGS, 16, 17. Lima (Limatula) hodgsoni. 



FIG. 16. Diagram of general anatomy. 



bi/.g., Byssal groove ; c., curtain of mantle ; e.g., cerebral ganglion : ij.d., genital duct ; 

 )/(., pallial muscle ; m.tl, diverticulum of mantle-cavity above lateral extremity of adductor ; 

 o., otocyst ; pc.c.. pericardia! communication ; p.<j., pedal ganglion ; p.r.p., posterior retractor 

 pedis ; r., renal organ ; r.c., communication between renal organs ; r.o., renal orifice ; 

 r.pc.d., reno-pericardial duct ; ., ventricle ; i:<j., visceral ganglion. 



FIG. 17. Diagram of mantle-diverticulum from behind. 



a., Anus ; <ib<l.o., abdominal sense-organ ; <nl<L, adductor ; br.a., gill-axis ; c., united 

 curtains of mantle ; in., pallial muscle ; w.d., di\'erticulum of mantle-cavity ; ., opening from 

 general mantle-cavity to diverticulum ; p.r.p., posterior retractor pedis. 



FIG. 18. Vencricardia purpurata. 



FIG. 18. Diagram of general anatomy. 



by.c., Byssal cleft ; li/.p., byssal papilla ; g.o., genital pore ; Jit., heart ; -i.p., inner palp ; 

 M.U., mantle-union; (.., otocyst; p.c., pericardium; r., kidney; r.c., renal communication ; 

 r.o., renal orifice : r.pe.iL, reno-pericardial duct. 



FIG. 19. Clilone (Chiintclrti) spinsa. 



FIG. 1'J. Diagram of general anatomy. 



app., Appendage to outer reflected lamina of gill ; g.o., genital orifice ; h., heart : 

 7.-.O., Keber's organ; o., otocyst; p.c., pericardium; r., renal organ; r.c., communication 

 between renal organs ; r.o., renal orifice ; r.pc.,1, reno-pericardial duct ; ., siphonal valves. 



