THE LAND SHELLS OF THE GENUS OBBA FROM MINDORO 

 PROVINCE, PHILIPPINE ISLANDS 



By Paul Bartsch 



Curator, Division of Mollusks and Cenozoic Invertebrates, United Slates National 



Museum 



Recent sendings to the United States National Museum of land 

 mollusks from Mindoro Province, Philippine Islands, for identifica- 

 tion have made it necessary to subject those belonging to the genus 

 Obba to a critical review; the results thereof are expressed in the 

 following pages. 



Mindoro Province includes besides the main island a number of 

 lesser isles and islets, and in order to get an adequate understanding 

 of the distribution of the various races of the species here discussed, 

 a relief map is here reproduced (pi. 87). It is hoped that this may 

 stimulate collectors to search for these and other land shells on the 

 small islands from which no mollusks have been reported. Such a 

 search is sure to produce rich results. 



KEY TO THE SPECIES OF OBBA REPORTED FROM MINDORO PROVINCE 



Shell acutely keeled at the periphery. 



Periphery with a dark band gallinula. 



Periphery without a dark band listeri. 



Shell not acutely keeled at the periphery. 



Shell angulated or rounded at the periphery. 



Periphery with a dark zone subhorizontalis. 



Periphery without a dark zone. 



Conspicuous brown marking absent sarcochroa. 



Conspicuous brown marking not absent. 



Subsutural interrupted brown band present mesai. 



Subsutural interrupted brown band absent. 



Upper surface very rough marmorata. 



Upper surface not very rough. 



Upper surface rather smooth planulata. 



OBBA GALLINULA BARTHELOWI, new subspecies 



Plate 88, Figure 1 



The shell is lenticular, strongly carinated at the periphery, rather 

 broadly umbilicated. The nuclear whorls are flesh-colored; post- 

 nuclear whorls of pale horn-colored ground color with a broad zone 

 halfway between the summit and the periphery, and a rather broader 

 peripheral zone of brown, which extends both on the upper and lower 

 surfaces in equal width and an almost median basal band, which is 



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