240 LYBOPUPA. 



Whorls 51/2, 1% embryonic, nearly smooth, marked by minute, 

 close, raised, spiral lines, the transverse ribs beginning abruptly 

 at this point. The last whorl tapers downward, and the latter 

 part ascends slowly towards the aperture; there is a broad, 

 shallow furrow extending for nearly % its length and ending 

 just back of the lip. The aperture is perpendicular, trun- 

 cate above, rounded below, peristome continuous. The inner 

 half of the parietal margin is appressecl to the pemiltimate 

 whorl, the outer half free. Angular lamella strong, erect, 

 long, slightly curved outwards in cross section, extending to 

 the outer margin; parietal lamella strong, somewhat curved 

 spirally. Columellar lamella very deeply seated, obliquely 

 placed on the columella, short. Upper palatal fold long, ex- 

 tending nearly to the margin of the aperture, slightly modi- 

 fied in front by the angular, with which it forms an almost 

 complete sinulus. Lower palatal long, low, much more deeply 

 seated than the upper and almost parallel with it. Peristome 

 more or less expanded on all sides, thin at the margin. 



Length 2.7, diam. 1.53, apert. 1.0 mm. 



Molokai: Pelekunu, type loc. (Forbes), Wailau Pali and 

 Kamalo (Cooke), Kalamaula (Thaanum, Pilsbry and Cooke), 

 fossil at the base of the Kalaupapa cliffs (Cooke) and top of 

 Mauna Loa (Pilsbry and Cooke). Type 11040, Bishop 

 Museum; Paratypes 24871 B. M. and 119456 A. N. S. P. 



There can be no doubt that this species is distributed over 

 the whole of the wooded portion of Molokai. Unfortunately 

 it has never been found in any number in any one locality 

 and in none of the lots are there more than half a dozen 

 specimens in most of them only 1 to 3. 



This species is, at first glance, very similar to some of the 

 forms of lyra-ta from Oahu. It is easily separated by the dif- 

 ferent sculpture of the embryonic whorls and the longer lower 

 palatal fold. 



3a. L. rhabdota plnris P. & C., n. subsp. PL 20, figs. 3, 4, 5. 



This short form of L. rhabdota is found along the pipe-line 

 trail, upper Kaunakakai. The summit is obtuse and rounded, 

 about as in L. thaa-numi. The spiral striae are weaker, less 

 regular than in typical L. rhabdota. 



