/■ 



JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. 11 Deckmber 19, 1921 No. 21 



ZOOLOGY. — A key to the Philippine operculate Imid mollusks of the 

 genus Ceratopoma.i Paul Bartsch, United States National 

 Museum. 



In 1918 we published in this Journal^ a Classification of the Philip- 

 pine operculate land shells of the family Helicinidae, with a synopsis 

 of the species and sub-species of the genus Geophorus. In that paper 

 we gave keys to the subgenera and species of the largest genus, namely, 

 Geophorus, of the subfamily Helicinidae. Since then enough ma- 

 terial has come to hand to enable us to similarly treat another genus, 

 namely, that of Ceratopoma, a key to the species of which is herewith 

 furnished (see page 502). 



Ceratopoma has the operculum less specialized than any other 

 Philippine Helicinid. It consists of a simple, horny shell without 

 calcareous deposit. The type of the genus is Helicina caroli Kobelt. 



The animal, like Geophorus, is usually a ground dweller and may 

 be found among dead leaves as well as in crevices of rocks. At the 

 present time the genus is known from Luzon, Leyte, Siargao and 

 northeastern Mindanao, and it is quite possible that careful collect- 

 ing in the islands between the two extremes will reveal additional 

 species. 



Ceratopoma caroli Kobelt comes from the island of Siargao. It 

 is a large species, with the parietal callus chestnut brown. In fact, 

 it is the only Ceratopoma so far known with a brown callus. 



Ceratopoma henningiana Mollendorff was described from Pena 

 Blanca, Luzon, and differs from all the other Ceratopomas in having 

 a broad brown basal band near the periphery. 



Ceratopoma cagayanica, sp. nov., differs from the other two 

 known large non-color-banded Ceratopomas in having the peripheral 

 keel limited on the base by an incised line, in which character it agrees 

 with Ceratopoma henningiana Mollendorff. The type, Cat. No. 



*■ Published by permission of the Secretary of the Smithsonian Institution. Received 

 November 8, 1921. 



2 This Journal 8: 643-657. 1918. 



501 



