766 GASTROPODA. [Pulmonata . 



which terminates in a strong tubercular tooth close to the base of the 

 rolumella ; the teeth and flange often subobsolete. Columella sloping, 

 concave, sometimes indistinctly folded above, far within ; parietal 

 callus strong, smooth. Sometimes an elongate umbilical fissure is 

 present. 



Diameter, 38 mm. ; height, 84 mm. ; length of aperture, 41 mm. 

 Diameter, 34 mm. ; height, 75 mm. ; length of aperture, 36 mm. 

 Diameter, 29 mm. ; height, 67 mm. ; length of aperture, 32 mm. 



Egg and Embryonic Shell. The egg is rather small, white, cal- 

 careous, roundly ovate, very finely granular, lightly shining, thin and 

 fragile ; diameter, 5 mm. ; length, 6 mm. Embryonic shell of 2 

 whorls, roundly ovate, subperf orate, finely and closely radially zigzag 

 striate ; the nucleus with a distinct inner raised angle and a central 

 elongated pit, the suture deep ; aperture rotundly lunate. 



Dentition. Button, T.N.Z.I., xiii, 200: xiv.' 152. pi. 3. f. D. 0; 

 xvi, pi. 9, f. B. 



Animal and Anatomy. Murdoch, P. Mai. S., iii, 324, pi. 16, f. 7, 8. 



Animal. Spirit specimen : The sides of body, neck, and tail black 

 and granulated, the lines of granules somewhat irregular and sloping 

 to the foot-margin ; tail depressed and somewhat pointed ; foot dull- 

 leaden colour ; ommatophores black, of medium length, genital pore a 

 little behind the right ommatophore. Mantle with an even margin ; 

 ;i small fold projects from the under-suri'ace, commencing at the re- 

 spiratory aperture, and extending almost to the dorsal line ; a corre- 

 sponding but smaller fold occurs on the left side ; respiratory and 

 anal apertures in the cleft of the right fold. (Murdoch.) 



Jaw arcuate, attenuated at the ends ; membranaceous, soft, ver- 

 tically striated by infoldings of the membrane, giving the jaw the 

 appearance of being composed of many pieces. 



Radula 4j mm. in breadth, and length about 2| times as much, 

 with about 140 transverse rows of teeth. These rows are nearly 

 straight, forming a very obtuse angle salient posteriorly. Teeth 

 55 + 1 + 55, of which 28 are laterals. The central tooth has a single 

 cusp, with rounded shoulders at its base ; the cutting-point is short 

 and broad ; the base of attachment broadens posteriorly, and does not 

 extend as far as the apex of the cutting-point ; the lateral teeth are 

 bicuspid, with the outer cusp small ; there is no cutting-point on the 

 interior cusp near the central tooth, but at about the twelfth row a 

 small cutting-point appears ; this gets larger to No. 20, then smaller 

 again, disappearing in the marginals altogether. At about the fortieth 

 row the central cutting-point disappears also. (Button.) 



Alimentary System. The buccal mass is large and muscular ; a 

 large salivary gland envelopes the oesophagus, with 2 salivary ducts 

 emptying into the buccal cavity. The stomach passes gradually 

 into the intestine ; the latter makes a left-hand spiral turn, passes 

 forward to the pulmonary chamber, thence back for nearly the full 

 length of the stomach, turns abruptly to the right, and proceeds as a 



