BY H. LEIGHTON KESTEVEN. 625 



The digestive tract (fig. 1) is esentially the same as in 

 Littorina. The buccal mass (figs. 1 and 6, hue.) is large; the 

 cartilaginous cushions on which the radula rides are shaped 

 like the quarters of an orange, the thin or lower end of the large 

 one on the right folding inside that on the left. There being no 

 introvert, the anterior oesophagus (fig. 6, ant. oes.) is very short. 

 It is provided with appendages (fig. 6, ajop.) similar to those 

 figured by Souleyet in Littorina (21). The crop (figs. 1 and 6, 

 cro-p) is the largest organ in the body cavity; it is of a brown 

 colour, and, as in Littorina^ the lumen is along its lower side; 

 the greater part of it is traversed and divided by thin partitions, 

 the attachment of which may be seen on the outside as slight 

 constrictions. The posterior oesophagus (figs. 1 and 6, j^ost.cts.) 

 passes along the axis of the visceral coil for about half its length, 

 when it enters the large, muscular-walled stomach (fig. 1, st.). 

 This latter is shaped like a segment of a circle an tero- posteriorly, 

 and flattened dorso-ventrally; its distal end is a little posterior 

 to the entrance of the oesophagus; anteriorly it tapers away to 

 the thin intestine. The intestine (fig. 1, int.) immediately rises 

 towards the superior face of the liver, and, having reached the 

 surface, traverses that face of it to which the nephridium is 

 attached, in the serpentine manner depicted in my figure; thence 

 the rectum passes along the right side of the pallial cavity, the 

 anus (fig. 1, an.) being situated well towards the end thereof. 

 The liver is dark green, and, as is usual, is the main constituent 

 of the visceral coil (fig. 1, liv.). The hepato-pancreatic ducts (fig. 

 1, h.-p.d.) are three in number — one at the extreme posterior end 

 of the stomach, one emptying into the centre on the superior 

 face, and the third situated well towards the anterior end, on the 

 axial side. The position of this last may sometimes be seen 

 from the outside. The salivary glands (figs. 1 and 6, sal.gl.) are 

 small; their ducts enter the buccal mass on either side of and 

 just anterior to the oesophagus. The radula (fig. 1, rad.) is 

 typically littorinoid, long (46 mm.) and narrow ; it leaves the 

 buccal mass on the underside and passes to the right of the body 

 cavity, where it is coiled up. The rachidian, as is stated in the 



