Description of Plates 175 



Fig. 45. — A. assimilis Ehlers, var. affinis Ashworth, from Table Bay, Cape 

 Colony. A portion of the alimentar\' canal, at the junction of 

 oesophagus and stomach, to show the multiple oesophageal glands. 

 The posterior part of the oesophagus is unusually extended. 



Fig. 46. — A. marina (Linnaeus). Dissection of the anterior end, from the dorsal 

 surface ; the buccal mass and pharynx have been cut away to show 

 the prostomium, oesophageal connectives, statocysts and septal 

 pouches. 



PLATE XIV. 



Fig. 47. — A. marina (Linnaeus). Section of the statocyst and the tube leading 

 to the exterior. The statoliths are naked irregular bodies, chiefly 

 quartz-grains; one (D) is a diatom (see p. 67). 



Fig. 48. — A. marina (Linnaeus). Fourth left uephridium, dorsal aspect. The 

 ventral lip (Nph. F.V.) of the funnel is seen through the dorsal 

 one (see p. 71). 



Fig. 49. — A. 2}iisilla Quatrefages (A. clajuircdii Levinsen). Ventral aspect 

 of anterior portion of third left ncphridium of a large specimen 

 (160 mm. long.) fiom Unalaska ; M. Band of muscle which binds 

 the funnel to the body-wall. 



Fig. 50. — .1. assimilis Ehlers. Ventral aspect of anterior portion of second right 

 nephridium, showing that the ventral lip of the funnel is thrown 

 into folds or frills (see p. 71). 



PLATE XV. 



Fig. 51. — A. branchialis Audouin and Edwards (A. grubii Claparede). Fourth 

 left nephridium, dorsal aspect. The deeply-notched ventral lip 

 (Nph. F.V.) of the funnel is seen through the dorsal one. 



Fig. 52. — A. ecaudala Johnston. Female specimen from Plymouth ; fifth right 

 nephridium with mature o\ary, dorsal aspect (see p. 73). 



Fig. 53. — ,4. ecaudata Johnston. Male specimen, from Plymouth; tenth left 

 nephridium, with mature testis, dorsal aspect (see p. 73). The 

 deeply notched ventral lip (Nph. F.V.) of the funnel is seen through 

 the dorsal one. 



