656 bartsch: classification of helicinidae 



The section in which incised spiral hnes are present embraces five 

 species coming from the islands of Luzon, Marinduque, Siquijor, and 

 Cebu, while the six belonging to the section that has no incised spiral 

 lines come from the islands of Luzon, Negros, Bohol, and Leyte. 



Of those having incised spiral lines, two are provided with collar 

 bands. One of these, Geophorus (Diplopifiax) acutus Pfeiffer, is much 

 larger than the other. A cotype. Cat. No. 104393, collected by Cuming 

 at Argao, eastern Cebu, has 5.5 whorls and measures: altitude, 8.3 

 mm.; greater diameter, 13.8 mm. The smaller banded form, Geophorus 

 (Diplopinax) alhocarinatus (Mollendorff) Wagner, comes from the 

 island of Siquijor. A specimen, Cat. No. 195505, having 5.1 whorls 

 measures: altitude, 6.6 mm.; greater diameter, 10 mm. 



Of the three unhanded species one, Geophorus (Diplopinax) bothropo- 

 mus Mollendorff, is quite large. Of this I have not seen specimens. 

 Wagner figures the operculum and gives the following measurements: 

 altitude, 9.5 mm.; greater diameter, 18 mm. It comes from Caramoan, 

 Luzon. The other two species are decidedly smaller. One of these 

 Geophorus {Diplopinax) conoidalis Mollendorff, has the spire decidedly 

 elevated and the base but very slightly rounded. A specimen of this 

 species. Cat. No. 258786, has 5.3 whorls and measures: altitude, 7.4 

 mm.; greater diameter, 10.8 mm. The last species, Geophorus {Diplo- 

 pinax) mollendorff in. sp., has the spire rather depressed and the base 

 strongly rounded. The type. Cat. No. 195503, comes from the island 

 of Siquijor. It has 5.1 whorls and measures: altitude, 4.9 mm.; greater 

 diameter, 9.8 mm. 



The section lacking incised spiral lines can be divided into a banded 

 and plain group. The banded group embraces three forms, of which 

 Geophorus {Diplopinax) peracutissimus Wagner is quite large. This 

 species comes from the island of Negros. A specimen. Cat. No. 302777, 

 having 5.1 whorls measures: altitude, 8 mm.; greater diameter, 14.6 

 mm. This has a faint brown band at the summit and another above 

 and below the periphery, a little within the edge. The other two forms 

 are of medium size. One, Geophorus {Diplopinax) cumingi n. sp., col- 

 lected by Cuming on Negros, has the color bands as in Geopkprus {Diplo- 

 pinax) peracutissimus Wagner, but the shell much more elevated. The 

 type, Cat. No. 302739, has 5.2 whorls and measures: altitude, 7.5 

 mm.; greater diameter, 11.2 mm. The third banded species, Geophorus 

 {Diplopinax) taghilleranus n. sp., has the last whorls suffused with red 

 and the interior of the same color. The type of this. Cat. No. 258760, 

 comes from Tagbileran, Bohol. It has 5.2 whorls and measures: alti- 

 tude, 7 mm.; greater diameter, 11.9 mm. 



