464 REV. A. H. COOKE ON [May 17, 



Phcenicobius bintuanensis. Hid. Peculiar. 



campanula, Pfr. Peculiar. 



Eulotella (l)fodiens, Pfr. Also occurs in Philippines. 

 Cochlostyla ^ satyrus, Brod. Palawan and Balabac. 

 Cyclophorus smithi, Hid. Peculiar. 

 CoptocMlus quadrasi, Hid. Peculiar. 



It is evident from this list that, as would be expected, PbSlippine 

 influence is preponderant in Busuanga. Of the 23 species known, 12 

 are peculiar, and, of the remaining 11, 2 are also peculiar to Palawan 

 and Balabac, 8 are common to the Philippines, and only 1 appears to 

 occur in Borneo. AmpJiidromus, which occurred in Palawan, is not 

 represented, but relationship with Palawan is sufficiently attested by 

 the one Cochlostyla and by Sadra polychron. The Indo-Malay Opis- 

 thoporus which reached Palawan appears to reach no farther. The 

 occurrence of the Biaphora section of Ennea, which is only found 

 elsewhere in Luzon, is a markedly Philippine element, Kaliella is a 

 thoroughly Indo-Malay genus, which occurs sparingly in Java, 

 Borneo, and the Philippines. The two species classified as Ti'ocho- 

 morphoides are of doubtful generic position. Originally described 

 as Trochomorpha, they were afterwards placed by their author in 

 Geotrochus. In seems better to assign them to the genus in which 

 Von Martens has placed several other Geotrochoid species (e. g. 

 bantamensis, Smith, from Bantam I., off Java, and niahensis, Godw.- 

 Aust., from N. Borneo), until their anatomy has become definitely 

 known. 



By far the most interesting part of the moUuscan fauna of 

 Busuanga are its Helices. Only three are known, viz. campanula, 

 Pfr., bintuanensis, Hid., polychroa, Sby. These three species 

 belong to two groups closely related to one another. One of these 

 groups is represented in Palawan, the other in Mindoro, Busuanga 

 uniting the two by possessing both. There can be little doubt of the 

 very close relationship of campanula and bintuanensis (together 

 with ceres, Pfr,, probably from this same locality) with the species 

 so long regarded as a group of Cochlostyla {Phcenicobius), but 

 now separated off by von Mollendorff as a group of Helices of the 

 Camcena family. The curiously stumpy form, thick and roughly 

 toothed lip, and often wrinkled sculpture are marked points of 

 similarity throughout. The other group, that of polychroa, is more of 

 the normal helicoid type, but is linked with Phcenicobius by the form 

 trailli, Pfr., which presents points of analogy with both groups. 



This occurrence of a number of large Helices of very restricted 

 distribution {Phcenicobius being peculiar to Busuanga and Mindoro, 

 and the polychroa group to Busuanga, Palawan, Balabac, and perhaps 

 N.E. Borneo) is exceedingly remarkable. The evidence that the 

 polychroa group extends to Borneo is not strong. H. trailli and H. 

 palawanica are given from Borneo in the Brit. Mus. on the authority 

 of Mr. Ussher, Consul at Labuan about 1 5 years ago. Issel, however, 

 in his monograph of Borneaa Mollusca, gives these same species, not 

 from Borneo, but from ' Stretto di Palawan,' which probably means 



^ As the var. fischeri, Hid. 



