Endodontn .} QA STROPO1 > A . (>89 



Type in the British Museum. 



Hob. North Island : Near North Cape ; Whangaroa (C. Cooper) ; 

 Wade ; Waitakerei Kange (H. S.) ; Waikato ; Toko, near Stratford 

 (R. Murdoch) ; Ngaputahi, Tuhoe-land (A. Hamilton). South Island : 

 Riccarton Bush and Dyer's Pass (H. S.) ; Akaroa (F. Suter). 



Subsp. Iredalia, Webster, 1908, 



Thaumatodon Iredalia, T.N.Z.I., xl, 1907 (1908), 256, pi. 21, f. 19-22. 



Whork 4, last descending. Colour horny, irregularly blotched with 

 dark brown. Protoconch 1J whorls, striated. Sculpture : Body-whorl 

 with growth-lines, spiral striations, and 13 strong ribs, which slope 

 backwards from the suture, and extend, sloping forwards, into the 

 umbilicus, which is pervious, and occupies one-fourth of the major 

 diameter. Aperture advancing slightly above. The body has 1 simple 

 lamella within the aperture ; it is hardly visible until the shell is 

 revolved so as to see well into the opening. (Webster.) 



Diameter Maj., 3-25 mm. ; min., 3mm. : height, 1-5 mm. 



Type in the Canterbury Museum, Christchurch. 



Hab. Ashley Gorge, Canterbury (T. Iredale). 



Remarks. The shell is a little more depressed and the whorls 

 more rapidly increasing than in the species. The chief characteristic 

 point is the small number of radiate riblets, which are reduced to 

 about half the number usually met with in E. raricosa. The umbilicus 

 is also slightly narrower. 



Subgen. 2. PTYCHODON. Ancey, 1888. 



Ptychodon, Ancey, Bull. Soc. Mai. France, v, March, 1888, 372. Type : 

 Strobila leiodus, Hutton. Strobila, Hutton, 1883 ; not of Morse, 1864. 

 it, Suter, 1890 ; not of Pfeiffer, 1855. Maoriana, Suter, 1891. 



Animal with peripodial groove, without caudal mucous pore. 



Jaw membranaceous, slightly arcuate, with distant vertical strife. 



Radula consisting of 90-100 slightly sinuous transverse rows of 

 teeth, the formula varying from 6 + 4+1 + 4+6 to 10+7+1 + 7+10. 

 Central tooth tricuspid. Lateral teeth similar, tricuspid. Marginal 

 teeth tricuspid or quadricuspid, the cusps showing a tendency to 

 coalesce on the outer ones. 



Shell discoidal, with low convex spire, umbilicated, rounded peri- 

 phery, and rib-striated surface ; aperture crescentic, subvertical ; 

 outer lip thin, simple, armed a short distance within with numerous 

 low folds ; columellar lip bearing 1 or 2 larger entering lamellae, and 

 parietal wall bearing 1 or 2 stout entering plates, sometimes emarginate, 

 or several smaller folds. 



Distribution. New Zealand ; Campbell Island. 



The species live under bark and rotten wood, in the bush. 



