THE COMMON MUSSELS. 45 



Plate V. 



17. Nervous system of M. latus. 



18. Nervous system of M. eclulis, after Duvernoy. 



19. Marginal nerves of M. latus (diagrammatic). 



20. Pedal ganglion and surrounding muscles of M. latus. 



Plate VI. 



21. Arterial system of M. latus. 



22. Anterior aorta and pallial arteries of M. eclulis. 



23. The same of M. magellanicus. 



24. Lateral view of arterial system of M. latus. 



25. Arteries of M. eclulis, after Sabatier. 



26. The same. 



27. Tentacular arteries of M. latus. 



28. The same. 



Plate VII. 



29. Pallial arteries of M. latus. 



30. Pallial arteries of M. magellanicus. 



31. Pallial arteries of M. eclulis, after Sabatier. 



Plate VIII. 



32. Venous system of M. eclulis, after Sabatier. 



33. Pericardium and longitudinal vein of M. latus (diagrammatic). 



34. The same of M. eclulis. 



Plate IX. 



35. Transverse vertical section of M. eclulis, showing gills (diagrammatic). 



36. Single gill-filament of M. lakes. 



37. Same as Fig. 35 of M. edulis. 



38. Single gill-filament of M. edulis, after Peck. 



39. Part of gill-plate of M. latus, just behind the middle retractor; the mantle is cut 



off by the base of the gill. 



40. Diagrammatic view of the arrangement of the middle interlarnellar junctions of 



M. latus. 



Plate X. 



41 to 44. Sections of M. eclulis. (See previous explanations.) 



By Authority : Geokge Didsbuby, Government Printer, Wellington.— 1887. 



