BULIMELLA. 119 



midal, the outlines of the spire more or less convex, at least 

 near the rather obtuse summit; embryonic whorls not eon-~ 

 spicuously flatter than those following; lip distinctly thick- 

 ened by an internal callous rib (except in A. abbreviata and 

 A. lila) , the outer edge often slightly expanded. 



Type: A. byronii rugosa Nc. Distribution: Entire Koolau 

 or Main range of Oahu. 



About forty-six names, most of them originally introduced 

 as "species", have been applied to members of the Bulimella 

 group up to this time. Mr. Baldwin, in his Catalogue of 

 1893, enumerated twenty-five species. Mr. E. B. Sykes 

 (1900) admitted twenty species and three varieties. In the 

 present monograph, thirteen species and eighteen subspecies 

 are recognized ; but this number includes two species and ten 

 subspecies not before published. Most of the other names are 

 synonyms, but a few may be retained for local forms thought 

 to be below the grade of "subspecies". A more rigorously 

 logical treatment might reduce the "good species" to nine, 

 by the union of viridans and taniolata; byronii, decipiens and 

 pulcherrima; and bulimoides and elegans; but the price of 

 such consistency would, I imagine, be the loss of clear con- 

 ceptions. 



Bulimella is a shell of the ravines as well as of the ridges, 

 and before the extensive deforestation of the lower slopes, 

 many fine species were to be found low in the valleys. This is 

 especially true of the bulimoides group, which formerly occu- 

 pied much territory now quite barren. The fuscobasis group 

 is almost confined to high ridges and peaks. 



The greatest development of Bulimella is in the northwest- 

 ern half of the Koolau range. There are but four species and 

 two or three subspecies in the whole southeastern third or 

 more of the length of the island, leaving nine species and 

 fifteen subspecies in the western five-eighths of the length. 

 Moreover, the differentiation has been greater in the west, 

 and doubtless new forms remain to be found there, whilst the 

 eastern part of the range has been so fully explored that no 

 new forms of Bulimella can be expected. 



Bulimella contains the most roughly sculptured species of 



