SuTER. — On New Zealand Mollusca. 135 



To judge from the number of whorls, the specimens are 

 not adult. 



Diaiiieter, greatest 2Jmm., least 2mm. ; height, IJmm. 



Hab. South Island : Mount Somers. 



I owe my specimens to the kindness of Mr. W. W. Smith, 

 of Ashburton, in whose honour the shell is named. This shell 

 is very distinct from all the other known species of Allodiscus. 



Jaw horse-shoe shaped, composed of about twenty-eight 

 vertical narrow plaits, indenting both margins ; a slight median 

 projection inferiorly; ends blunt. 



Madula tongue-shaped, the transverse straight rows of teeth 

 consisting of 15 — 1 — 15, of which four are laterals. Central 

 tooth rectangular, longer than broad, tricuspid, the median 

 cusp with its short cutting-point extending to the posterior 

 end of the base ; side-cusps short, sinuated, one minute cutting- 

 point on each. Laterals broader than the rhachidian, tri- 

 cuspid, but the inner cusp rudimentary and without cutting- 

 point, median cusp with a short cuttmg-point overlapping a 

 little the next row of teeth, outer cusp and cutting-point some- 

 what larger than in the central tooth. Marginals much 

 broader than long, with a tridentate cutting-point and some- 

 times a minute denticle on the outer side of the base. 



6. Allodiscus rusticus, n. sp. Plate XX., figs. 37-376. 

 Shell small, subdiscoidal, perforated, not shining, pale- 

 horny, thin, semi-transparent, with close radiate ribs, about 

 eight per millimetre, slightly sinuated and somewhat directed 

 backwards ; interstices with fine growth-lines, not reticulated. 

 Spire almost flat, embryonic whorl smooth ; periphery rounded. 

 Whorls 5, slowly and regularly increasing, flatly rounded ; 

 suture impressed, last whorl not descending in front. Aper- 

 ture oblique, lunar ; peristome simple, acute, columella margin 

 slowly ascending, callous, not reflexed. Umbilicus very nar- 

 row, open, previous. Base rounded. 



Animal unknown. 



Diameter, greatest 4|mm., least 4mm. ; height, 2^mni. 



Hah. North Island : Thames (T. F. Cheeseman). 



Note. — This species is very near A, godeti, milii, but the 

 spire is a little more elevated, the riblets are sinuated, directed 

 backwards and low, whilst almost straight, elevated in A. godeti; 

 in the latter the interstices between the ribs are reticulated, 

 and the embryonic whorl is spirally striated. A. rusticics has 

 much flatter whorls, and the suture less impressed. 



7. Charopa anguiculus, Eeeve, var. fuscosa, n. v. 



The specimens obtained are not adult, but have only 4 

 whorls. The colour is uniformly fuscous, but in all the other 

 characters they agree with Eeeve's and Hutton's (Trans. 



