716 



ZOOLOGY 



SECT. 



The coelome (Fig. 634) is a pouch of considerable size, divided 

 by a constriction into oral and aboral parts. The former is the 

 pericardium or cavity in which the heart is lodged : it gives off 

 a pair of diyerticula, right and left, each lodging the corresponding 

 branchial heart. The aboral part of the coelome forms the capsule 

 which encloses the ovary or testis. 



iiifca-rl 



te- 



FII;. i ;_';.. Sepia cultrata, ma'e specimen seen from the posterior aspect, the mantle-cavity 

 opened as in Fig. il'-H, the posterior body-wall partly dissected off, so as to expose the organs 

 in the visceral sac, the ink-sac and duct removed, ao >i. main aorta; <n-t.' aboral aorta 

 HII/L appendage of left branchial heart; <<. csecum ; iiif, nui. funnel cartilages; Hi: liver 

 '. iiini. !-. left abdominal vein; /. njf. In-, left afferent branchial vessel; /. aw. left auricle 

 /. In: kt. left branchial heart ; /. i-tm. left ctenidium ; /. .it. a. left stellate ganglion : mant. 

 fitrt. mantle cartilage; pen. penis; jtrnxf. prostate; /. <iini. v. right abdominal vein ; /. cten. 

 right ctenidium ; ,-. sen. n/i/i. appendages of right afferent branchial vessel; te. i: vein to 

 testis; i-ii. valve of mantle ; i\nt. ventricle. , 



The paired, plume-shaped ctenidium lies parallel with the long 

 axis of the body. It is attached throughout the greater part of its 

 length to the w T all of the mantle-cavity- by a thin muscular fold. 

 It consists of numerous pairs of delicate lamellae, the surface of 

 which is increased by the presence of a complex system of foldings. 



