PARTULINA, LANAI. 



species because in the large series of both species seen the in- 

 tergrading specimens are comparatively very rare. Nearest to 

 Koela the white form occurs, further along the ridge the 

 darker forms. Either sinistral or dextral forms may pre- 

 dominate in different colonies. Fig. 13 is copied from New- 

 comb's type figure. Figs. 1-4, 15 are from specimens taken 

 by Mr. Thaanum. 



45a. Var. hayseldeni Baldwin. PI. 21, figs. 5 to 12. 



" Shell sinistral, minutely perforated, rather solid, ovately 

 conical, apex subacute ; surface shining, marked with delicate 

 incremental striae, and under a lens exhibiting very close, 

 minute, decussating spiral lines; embryonic whorls faintly 

 cross-lined. Color generally of a uniform reddish-brown; 

 sometimes the coloring of the middle portion of the whorl 

 shades into white on the apical whorls, and in some examples 

 a white line revolves below the suture. Whorls 5^, slightly 

 convex, narrowly margined above, the last carinated or angu- 

 lated at the periphery, the angle becoming almost obsolete 

 towards the aperture ; suture distinctly impressed and often 

 margined above by the continuation of- the peripheral keel. 

 Aperture oblique, subovate, white within with a pinkish tinge ; 

 peristome white, rather obtuse, thickened within, the basal 

 and columellar margins slightly reflexed; columella termin- 

 ating in a strong, flexuous, white fold. Length Yl l / 2 , diam. 

 10 mm. 



" Animal when extended in motion longer than the shell. 

 Mantle slate color with a brown band encircling the outer 

 edge. Foot above and below almost white with a yellowish 

 tinge. Tentacles white tinged with slate ' (Baldwin). 



Lanai (Walter H. Hayselden) ; Lanaiha'le, near highest 

 point of mountain (Perkins, Thaanum). 



Partulina hayseldeni BALDWIN, Nautilus, x, p. 31, July, 

 1896. Achatinella (Partulina) hayseldeni Baldwin, SYKES, 

 Fauna Hawaiiensis, p. 313, pi. 11, f. 2. 



This species is allied to P. semicarinata Newc., which is 

 found in another district of the same island. The latter is a 

 light straw-colored, more conical, and invariably dextral 



