PLATE XV. 



(51. — Longitudinal section of the tip of the second cirrus of the spadix. ('. L. > 14. 



( i, gland. 



N, nerve. 

 Fig. 62. — Longitudinal section through a crypt and its tongue of the third cirrus of the spadix. ('. L. > 35. 

 Fig. 63. — Longitudinal section of the base of the preocular tentacle. ('. L. X 20. 



X, nerve trunk. 



.V, nerve bundles running along the anterior side of the nerve trunk. 

 64.— Longitudinal section of the tip of the preocular tentacle. < '. L. ■ 20. 



\. artery. 



ii.. ciliated groove on anterior side. 



i ;. groove "i! posterior side. 



X, nerve. 



n, branch nerve to the peripheral portion of the tentacle. 



It, ridge on anterior side of tenfacle. 



V, vein. 



X. breaking plane. 

 Fig. 65.— Slightly oblique cross section of the preocular tentacle about 6 millimeters from its tip. ('. L. X 35. 



('( i. ciliated groove between the upper and lower projecting ridges, R and It'. 



X, nerve. 



V, nerve bundles running along anterior side of nerve. 



It. base of projecting ridge. 



It', upwardly projecting portion of the next lower ridge. 



