Journal of conchology . eto the genital papilla, is a second gill-like organ about 3 mm. longand mm. wide, composed of about ten lamellae. It is apparentlyan osphradium. The renal organ is composed of numerous fineramifying tubes. The pericardium and heart apparently lie in theleft anterior part of the mantle chamber, but could not be identifiedwith certainty in any specimen. The buccal mass is 7 mm. long and 5 mm. broad. It is notstriated. The mouth opens into a spacious chamber with puckeredwalls. The deep brown radula consists of a single series of from 22to 25 teeth, of which from 10 t
Journal of conchology . eto the genital papilla, is a second gill-like organ about 3 mm. longand mm. wide, composed of about ten lamellae. It is apparentlyan osphradium. The renal organ is composed of numerous fineramifying tubes. The pericardium and heart apparently lie in theleft anterior part of the mantle chamber, but could not be identifiedwith certainty in any specimen. The buccal mass is 7 mm. long and 5 mm. broad. It is notstriated. The mouth opens into a spacious chamber with puckeredwalls. The deep brown radula consists of a single series of from 22to 25 teeth, of which from 10 to 15 seem to be in use. It is notascoglossan ; the anterior teeth show signs of being worn out, andno doubt disappear in the usual way. Seen in the profile the teethare very erect. (Text Fig. 6). The back part of each is broad atthe base and hollowed out so as to receive the anterior part of thesucceeding tooth. Each tooth bears from three to five denticleswhich are sometimes rather irregular in shape and almost Text Fig. 6.—Three teeth of Newnesia antarctica. There are no jaws and no buccal crop. The salivary glands arewhitish, thick, and foliaceous, about 4 mm. long and mm. broad,with very short ducts. On leaving the buccal mass, the alimentary tract dilates at onceinto a large tube which is bent on itself. The first bend (5 mm. longand mm. broad) bears a smooth diverticulum on the top mm. high. The second bend is 8 mm. long and 3 mm. tube bears inside about ten longitudinal lamellae studded withprominences. Inside the lamella can be seen yellowish foUiculatebodies which are apparently glandular. Somewhat embedded in the front of the liver, but not enclosed byit, is the small round stomach. The interior is lined with irregular 314 JOURNAL Of CONCttOLOGY, VOL. II, NO. 10, APRIL, 1906. soft folds, but shows no trace of plates. From it issues the intestine. Round the buccal mass is set a collar of ganglia consisting of threepairs on the top
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Keywords: ., bookauthorconcholo, bookcentury1800, bookdecade1870, bookyear1879
