ATLANT. DEEP-SEA EXPED. 1910. VOL. III]. 



PTEROPODA. 



59 



B 



Fig. 49. Median and lateral teeth of A. Cephalobrachia macrochaeta, and B. Clione limacina 



(drawn to the same scale). 



Clionidae. 



Radula: Median tooth triangular, the base of the 

 tooth forming one side of the triangle while the two other 

 sides are formed by its free borders (textfig. 49). 



No jaw. 



Hook-sacs oviform, all the hooks reaching the 

 opening of the invaginated sac. 



No acetabuliferous appendages. 



No lateral gill. 



Clione Pallas. 



Radula with a great number of very small teeth. 

 Free border of the median tooth with a denticle protruding 

 from the bottom of an incision. 



3 pairs of buccal cones. 



Clione limacina Phipps. 

 PI. VIII, fig. 59-60. 



Radula: Lateral teeth narrow pointed hooks, the 

 number in each transverse row varying between 10 and 

 14 (textfig. 50). 



Foot with broad lateral and rudimentary posterior 

 lobes. 



No gill. 



Fig. 50. Radula of Clione limacina. 



