264 LYROPUPA. 



base. The Rocky Hill example figured, pi. 23, fig. 7, is one 

 of the most strongly sculptured. 



17a. L. micro, percostata P. & C., n. subsp. PL 25, figs. 11, 12. 



The ribs are more prominent than in L. micra, more separ- 

 ated, often in pairs. There is a prominent dorsal hump, below 

 the middle of the last whorl. The parietal lamella is deeply 

 placed, high within, its free edge flaring towards the suture. 

 Columellar lamella immersed, vertical, nearly straight, the 

 ends very weakly bent forward. Upper palatal fold about, 

 one-third of a whorl long. Lower palatal a small, low and 

 indistinct rounded callus, deeply immersed. Basal fold 

 deep within, blunt and elongate. There are well-developed 

 tubercles below the inner end of the upper palatal fold, be- 

 yond the lower palatal and basal. 



Length 1.8, diam. 0.9 mm.; 5 whorls (type). 



Length 2 mm. ; 5% whorls. 



Oahu : Kaelepulu, Kailua, on a lime-rock bluff about a 

 quarter mile from the shore ( Pilsbry ) . 



Chiefly distinguished by its sculpture. This and the less 

 strongly ribbed L. micra are abundant in the same Holocene 

 deposit, without intergrading forms. 



176. L. micra maunaloae P. & C., n. subsp. PI. 25, figs. 8, 9. 



The Molokai form is somewhat more sharply sculptured than 

 that of Oahu, and there are low protractive waves below the 

 suture on the last whorl or two, or the riblets are grouped by 

 fascicles there. 



Length 1.95, diam. 9 mm. (type, fig. 9). 



Length 1.75 mm. 



Length 1.9, diam. 0.97 mm. ; 5 whorls. 



Molokai: summit of Mauna Loa, and at Moomomi on the 

 north shore, near sea level (Cooke & Pilsbry) ; near the shift- 

 ing sands, Mauna Loa (Cooke). Pleistocene ?, and on the 

 summit of Mauna Loa later, within the human period, though 

 now extinct. 



Some of the examples from Moomomi are a little larger 

 2 to 2.1 mm. long. 



