53 



1 897- Dentalinm indicuin Chenu, Illustr. Conchyl. I, Dentalium p. 4, pi. 3, fig. 11. 



? Dentalium novae hollandiae Chenu Illustr. conchyl. I, p. 5, pi. 6, fig. 14. 

 i860. Dentalium Philippinarum Sowerby, Thes. Conch. Ill, p. 98, pi. 225, fig. 54. 

 1S72. Dentalium Philippinarum Reeve's Conch. Icon. XVIII, pi. 3, fig. 18. 

 Not Dentalium eburneum Deshayes Mem. See. Hist. Nat. Paris 1825^/?. politum Linnc. 



Stat. 4. Anchorage ofi" Djankar (Java) 7°42' S., II4°I2'.6E. 9 Metres. Coarse sand. 2 Spec. 



Stat. 174. Waru-bay, North coast of Ceram. 18 Metres. Mud. 2 Spec. 



Stat. 294. io°i2'.2S., 124° 27'. 3 E. Timor Sea. 73 Metres. Soft mud with very fine sand, i spec. 



Stat. 296. Anchorage off Noimini, South coast of Timor. io°i4'S., 1 24° 5'. 5 E. Sandy mud. 4 Spec. 



Diagnosis. Shell long and slender, moderately arcuate, attenuated posteriorly, the 

 length about i2Vj times the diani. ; rather thin; white, shining. Sculpture of numerous, unequal, 

 irregularly spaced encircling ribs, rather low and rounded, with fine growth lines throughout; 

 sometimes showing traces of longitudinal striation in places. Aperture subcircular or rounded- 

 ovate, narrower toward the concave side ; peristome thin. Anal orifice small, rounded-oval, the 

 greatest diameter antero-posterior ; a slight notch on the convex side or none. 

 Length 95, antero-posterior diam. apert. 4,7, lateral diam. 4,5, diam apex 0,9 mill. 

 Length 66, diameters of apert. 5,3 of apex 0,9 mill. (P. & .Sii.). 



Distribution. Singapore; Sullivan Island, Mergui Archipelago in 7 fms (Anderson); 

 Siam ; Philippines ; Java. 



Remarks. This species is easily recognised by the numerous circular swellings of the 

 tube. Generally after each .swelling there is a more deeply incised growthline. 



I hold D. Philippinariiin Sowb. to be onl)- a name for young specimens of eburneum. 

 Most of the Siboga specimens are young; they are reddish or golden brown, much attenuated, 

 very narrow and sometimes striated near the apex. In older specimens the colour becomes 

 lighter, the diameter increases proportionally and the elevated concentric rings become stronger. 



Sowerby thus describes it ; 



D. P hillippinariDJi Sowerby. 



Shell elongated, very narrow, rather .straight, semipellucid, highly polished, somewhat 

 golden brown banded with numerous elevated concentric rings ; apex attenuated ; apical fissure 

 very short. 



I s 1 . S a m a r , Philippines. 



Generally of a darker golden brown colour, much narrower and straighter than Denla- 

 lium ebtirneum. 



Several fine specimens of D. eburnetttii are at the Zool. Mus. of Amsterdam. One of 

 these struck me as rather peculiar : in place of the low variceal rings, the tube shows only 

 some irregularities of growth, while the apex is striated. The surface is very smooth and brilliant 

 with numerous inconspicuous growthlines. The growthlines are at regular distances and rather 

 deeply incised. Toward the anterior aperture the tube shows tendency of forming concentric 

 rings. This fact convinced me that this shell, though distinguished by some minute details, 

 belongs to D. cbitnictini. 



