Laoma.] GASTROPODA. i ''' 



1. Group of Laoina Marise. 

 Shell imperforate. 



KEY TO SPECIES. 



A. Shell smooth ; periphery convex . . . . . . lucida. 



B. Shell costate or rib-striate ; periphery angled or carinated. 



a. Shell minute, with membranous riblets, 8-10 per millimetre ; 



periphery angled . . . . . . . . . . filicosta. 



b. Shell larger, with fine rib-stri;i\ 20 per millimetre ; perpihery 



acutely keeled . . . . . . . . . . Maria. 



1. Laoma filicosta, Suter, 1907. Plate 11, fig. 3. 



Laama (Phrixgnathus) filicosta, Suter, P. Mai. S., vii, 1907, 236, pi. 22, 

 f. 3. 



Shell minute, turbinate, imperforate, fulvous, with fuscous radial 

 streaks and distant riblets. Sculpture consisting of very fine and 

 oblique flexuous riblets, 8 to 10 per millimetre ; they are sharp, thin, 

 membranous, white, and extending over the base to the umbilical 

 region ; the interstices with numerous microscopic incremental stiise ; 

 protoconch and base with spiral lirse. Colour fulvous, radially orna- 

 mented with zigzag bands of rufous at about the same distance apart 

 as the riblets. Epidermis thin, not shining. Spire convexly conoidal, 

 with a blunt and rounded apex, its height equal to that of the aperture. 

 Protoconch of 1J smooth flat volutions. Whorls 4J, slowly and regu- 

 larly increasing, flatly convex, the last distinctly angled at the peri- 

 phery ; base rounded, umbilical region slightly impressed. Suture 

 not deep. Aperture somewhat oblique, lunate. Peristome sharp, 

 straight. Columella short, arcuate. Inner lip but little callous, ex- 

 tended over the umbilical region. 



Diameter, 1-75 mm. ; height, 1-25 mm. 



Animal unknown. 



Type in my collection. 



Hob. North Island : Wairangi, Waikato, in a swampy kahikatea 

 bush (A. Suter). 



2. Laoma lucida, Suter, 1896. Plate 10, figs. 8, ., b. 



Laoma (Phrixgnathus) lucida, Suter, P. Mai. S., ii, 1896, 36, pi. 4. 

 f. 13-15. 



Shell very small, depressed turbinate, imperforate when adult, 

 yellowish-horny, smooth, pellucid, shining. There is no sculpture. 

 except microscopic growth-lines without spiral striation. Colour 

 uniformly yellowish-horny. Spire conoidal, of about the same height 

 as the aperture ; outlines lightly convex. Protoconch smooth, convex. 

 Whorls 5, gradually increasing, convex, periphery rounded. Suture 

 rather deep, very narrowly margined below. Aperture oblique, lunate, 

 transverse. Peristome straight, acute, somewhat callous inside. 

 Columella very short, oblique, arcuate. Inner lip with a white 



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