fs. Filament support, probably to keep the filament from swelling into 



a cylindrical shape with the pressure of the blood, 



fv. Foot vein. 



g. Gill. 



gf. Gill filament. 



i. Intestine. 



ifj. Inter-filamentar junction. 



ig. Inner gill, 



ilj. Inter-lamellar junction. 



io. Inhalent ostium. 



ir. Infolded ridge of the mantle. 



1. Liver. 



le. Lens. 



Im. Longitudinal muscles. 



Ip. Labial palps. 



Iv. Left valve of the shell. 



m. Mantle. 



mf. Muscle fibers. 



n. Nerve. 



DC. Ostium cilia. 



oe. CEsophagus. 



eg. Outer gill. 



on. Optic nerve. 



ot. Otocyst. 



otn. Otocystic nerve. 



p. Pericardial cavity. 



pa. Posterior adductor muscle, anterior portion, 



pa'. Posterior adductor muscle, posterior portion, 



paa. Posterior adductor artery. 



pas. Posterior adductor muscle scar, anterior portion, 



pas'. Posterior adductor muscle scar, posterior portion 



pav. Posterior adductor muscle vein, 



pg. Pedal ganglion. 



pi. Pallial line, 



pn. Palp nerve, 



ppa. Posterior pallial artery, 



ppn. Posterior pallial nerve, 



pps. Posterior pallial scar, 



pv. Pallial vein. 



r. Retina. 



rpm. Radial pallial muscles. 



rv. Right valve of the shell, 



s. Stomach, 



sg. Shell gland. 



sm. Suspensory membranes of the gills, 



sms. Suspensory membrane scars. 



^7 



