PHYLUM MOLLUSCA 



reel 



733 



FIG. r.42 />/.*. Nautilus pompilius (male), origin of pallial and genital arteries ; ant. pal. a. 

 anterior pallial artery ; iff. (>/. <. efferent branchial veins ; gen. a. 1, artery to vesieula 

 seminalis (r. . ,/<.) ; <i< ,\. a. -2, testicular artery and its branches ; gen. a. 3, artery to pyriform 

 sac ; n. s. spermatophore sac ; i><>xi. ////. a. posterior pallial artery ; pyr. pyriform sac : , </. 

 rectum ; test, testis. (After Willey.) 



L.n-eph..afj 



Fio. 643. Nautilus poxnpilius, renal sacs, with ctenidiaand other related parts, as seen from 

 the posterior aspect ; the boundaries of the four renal sacs represented by dotted lines. 

 (i. 1. aff. left oral afferent vessel ; cUn. right ctenidia ; /. ncph. s. left nephridial sac ; 

 /. nepk. ap. left oral nephridial aperture; I. post. /><_j>/<. ap. left aboral nephridial 

 aperture; 1. post. ncph. s.' left aboral nephridial sac; p. I. nff. left aboral afferent vessel; 

 p. r. aff. right aboral afferent vessel ; /. n,it. jt\ right oral afferent vessel ; /. ant. aur. right 

 oral auricle; ren. app. renal appendages; ,'. nepk. <(p. right nephridial aperture; r. pout, 

 neph. s. right aboral nephridial sac ; /. v. up. right viscero-pericardial aperture ; ven. c. vena 

 cava ; vent, ventricle. 



