62 



Remarks. The difference of locality made me hesitate whether the Siboga specimens 

 could be identified with Entalina platamodes Watson. After comparison with the type in the 

 British Museum however, it is no longer doubtful that this species, hitherto only reported from 

 the W. -Indies and the Gulf of Mexico, is also distributed in the East Indian Archipelago. 



The Siboga specimens are very large ; they are well-curved and longitudinal striae, generally 

 12 in number, regularly cover the whole of the concave side. Anterior aperture indistinctly 

 pentagonal; generally a very faint angularity in the middle of the inner margin. Apex pentagonal ; 

 anal orifice generally simple, but two specimens have a short notch on the convex curve. 



*2. Entalina niirijica Smith. PL II, fig. 37. 



1895. Dentalium mirificum E. A. Smith, Ann. Mag. Nat. Hist. (6), XVI, p. 9, pi. 2, fig. i. 

 1897. Entalina mirifica E. A. Smith. PiLSBRV & SHARP, Man. of Conch., vol. XVII, p. 134, 

 pi. 20, fig. 29. 



Diagnosis. Shell small, strongly curved and acuminate toward the apex, quadrate 

 tubular, wider along the inner curve than along the outer; longitudinally delicately striate, very 

 delicately sculptured with growth-lines; subconcave between the angles. Length ly, greatest 

 diam. 2V2 mill. (Smith). 



Distribution. (3ff Trincomalee Ceylon 200 — 350 fms. 



This little species is remarkable for the sharply curved end and the subquadrate form. 

 The four angles are acute at the tip, but gradually become obtuse as the shell increases. The 

 incurved side is the broadest of all, and up the middle of it, especially towards the apex, there is 

 a raised striation more conspicuous than the rest. This is so prominent at the end that, when viewed 

 with the opening towards the eye, five angles are visible. The two angles on the excurved side, 

 which is the narrowest of all, become almost obsolete near the aperture. The form of the aperture, 

 owing to the greater width and flatness of the incurved side, is very like the letter D. (Smith). 



3. Entalina qtiadrangularis n. sp. PI. VI, figs 73, 74, 75, 85, 86. 



Stat. 88. o°34'.6N., 119° 8'.5 E. Celebes Sea. 1301 Metres. Fine grey mud. i Spec. 



•Stat. 151. o°i2'.6S., 1 29° 48' E. Halmahera Sea. 845 Metres. Fine grey mud with coarse 



particles, i Spec. 

 Stat. 256. 5°26'.6S., 1 32° 32'. 5 E. oft" Kei-islands. 397 Metres. Greyish green mud. i spec. 



Diagnosis. Shell white, rather strongly curved, decidedly quadrangular with a flat 

 e.xcurved, two flat lateral and a flat incurved side. The incurved side is widest 

 and has near the apex an obtuse longitudinal angle, the shell being there faintly 

 pentagonal. This angle disappears before the shell's middle is reached. All the 

 sides are finely longitudinally ribbed, the ribs rounded very narrow, separated 

 ^'^' ^ ■ bv wider interstices. Anterior aperture distinctlv quadrangular, the lateral sides 



Ant. apert. of Entalina ■' ^ . ti o i 



quadrangiiiaris. slightly coucavc. Apex pentagonal, simple. 



a. Length 19 mill.; breadth of aperture along the inner margin 2,7, along the outer margin 1,1 mill. 



b. Length 16 mill.; breadth of aperture along the inner margin 2,8, along the outer margin 1,5 mill. 



c. Length i 2,5 mill.; breadth of aperture along the inner margin 2,4, along the outer margin 1,1 mill. 



