sitter: new Zealand flammulina. 285 



In the nearly allied F. chorda fit, Pfr., I found the same microscopical 

 structure as in F. pilida, but the riblets are stouter, cord-like, still 

 less equidistant, from 6 to 8 per millimetre, never more. The very 

 narrow perforation is partly or entirely covered by the columellur 

 reflection. Diam. 4, alt. 3 mm. 



2. Flammulina (Piienacohelix) Ponsonbyi, n.sp. 



Patula irilula (Reeve): Hutton, Trans. New Zealand Inst., vol. xvi, 

 p. 161, pi. ix, fis'. K; pi. xi, fig. M (radula and jaw). 



Fruticicola pilula (Eceve) : Hutton, Trans. New Zealand Inst., vol. xvi, 

 p. 194. 



rhenacolteUx pilula (Reeve) : Hedley & Suter, Proc. Linn. Soc. New 

 South Wales, ser. ii, vol. vii, p. 641. 



Flammulina {Phenacohelix) pilula (Reeve) : Pilsbry, Man. Conch., 

 ser. II, vol. ix, p. 16, pi. iii, fig. 13 (the spire is usually 

 more depressed than here shown) ; also pi. ii, figs. 6, 7 

 (jaw and radula). 



Shell small, dopi'essed- globose, moderately umbilicated, obtusely 

 angled at the periphery, pale horny with irregular radiate dashes and 

 spots of rufous on the upper surface, passing over in zigzag lines at 

 the base, sometimes imparting a tessellated appearance to it, and 

 extending to the umbilicus; thin, dull. "Whorls Ah, regularly in- 

 creasing, flatly convex, sculptured with numerous arcuate, sub- 

 equidistant, tliread-like riblets, about 8, rarely 7 or 6, per millimetre, 

 Protoconch with numerous fine, microscopic, spiral striae, interstices 

 between the riblets microscopically decussated. Suture impressed ; 

 spire scarcely elevated. Last whorl obtusely angled above the middle, 

 not descending in front. Aperture oblique, lunate. Peristome thin, 

 sharp, slightly reflexed near the umbilicus, which is quite open, 

 slightly perspective, and about one-fifth of the greatest diameter. 

 Base convex. Diam. maj. 6, min. 5'25mm. ; alt. 3'25 mm. 



ILah. — North Island : — Whangarei ; Auckland ; JMt. Wellington 

 Lava Pields and Hillyer's Creek, near Auckland; Ilunua Range; 

 Oliaupo ; Mt. Taupiri ; Otaki Gorge ; Forty Mile Push ; Wanganui ; 

 Napier. 



The ty]:)e, from Mt. Wellington Lava Fields, is in ray collection. 

 The specimen figured is in the Pritish Museum (Natural History). 



Mr. J. H. Ponsonby, in whose honour the shell is named, was the 

 first to point out that the shell which we in New Zealand took for 

 F. pilula, Reeve, did not correspond with the type in the British 

 Museum, and I am greatly indebted to him for his kind assistance in 

 settling the question. 



A nearly allied species is Flammulina (^Allodiscus) ITossi, Murdoch, 

 (ante, p. 162), in which, however, the umbilicus is much narrower. 



Var. unicolor, Suter. 



Fhenacohelix pilula (Reeve) var. unicolor, Suter : Trans. New Zealand 

 Inst., vol. xxvi (1894), p. 134. 

 i7«J.— North Island; Mt. Taupiii. 



