82 



COMPARATIVE ANATOMY 



CHAP. 



11 



ill 



FIG. 78. Pallial complex and siphon of Nautilus pompilius ? (after Bourne and Lankester). 

 v, Valve of the siphon ; ro, right genital aperture ; m, the mantle fold, with the nidamental gland, 

 folded back ; an, anus ; cp, left aperture of the secondary ccelom ; Ihn, left upper nephridial aper- 

 ture ; lo, aperture of the left rudimentary oviduct ; Ivn, left lower nephridial aperture. The four 

 ctenidia are not lettered. 



FIG. 79. Pallial complex of Nautilus pompilius <J (after Bourne and Lankester). pe, Penis ; 

 a, muscle band of the siphon ; Isp, aperture of the left rudimentary seminal duct ; nrplm, m.'^Jifi. 

 lower and upper nephridial aperture of the left side ; olf, left osphradium ; viscper, left aperture of 

 the secondary ccelom ; an, anus ; x, supra-anal papilla of unknown significance ; c, mantle cut off. 



