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denticle which is separated from the body, by a distinct sinus; the outer one has 8 or 9 denticles 

 and a very thin plate of an elongate, triangular shape. If the teeth lay in their natural position 

 the uncini cover each other in such a degree, that their arrangement is scarcely clear, so it 

 might be that I have erred in the appreciation of what is the inner and outer of the uncini. 

 This description agrees only in part with that of the radula of Planaxis by Troschel (Gebiss 

 der Schnecken, Vol. I, p. 150, 151, PI. 12, fig. 7 — 9), for though the rhachidian tooth is really 

 of the same construction, the uncini are quite different by the lateral appendices. In this respect 

 they better agree with Cerithidea and Pyrazus (I.e. PI. 12, fig. 4 and 5), I have consequently 

 not followed the example of Fischer (Manuel de Conchyliologie) Tryon (1. c) and others, who 

 consider Qiioyia as a subgenus of Planaxis ; I think that its conchological character of the 

 plicated columella, together with the differences in the radulae, will be fully sufficient, to keep 

 them separate. 



Fam. MoDULiDAE. 

 Modulus Gray. 



I. Mod^ilus tectmn Gmelin. 



Gmelin. Syst. Nat. Ed. XIII, p. 3569. 



Tryon. Man. of Conch. Vol. IX, p. 260, PI. 48, fig. 87. 



Stat. 37. Sailus-Ketjil, Paternoster-islands. 27 M. Coral and coralsand. i Spec. 

 Stat. ? I Spec. 



Both specimens are still young, that from Stat. 37 is moreover broken, but sufficiently 

 characteristic. 



Fam. Triphoridae. 

 Triphora Blainville. 



1. Triphora (Eiithymia) princeps Sowerby. 



Sowerby. Proc. Mai. Soc. Lond. VI, 1904, p. 174 (fig.). 



Stat. 60. Haingsisi, Samau-island. Reef, i Spec. 



The only specimen, though young (it has only a length of 24 Mill, instead of 57) is still 

 a giant in the genus. Sowerby (1. c.) did not know the habitat of this species, described after 

 a specimen, from the collection of the late admiral Keppel. 



2. Triphora (Euthymia) sculpta Hinds. 



Hinds. Ann. and Mag. of Nat. Hist. Vol. XI, 1843, p. 17. 

 Tryon. Man. of Conch. Vol. IX, p. 178, PI. 37, fig. 82, 83. 



Stat. 250. Kilsuin, West coast of Kur-island. 27 M. Coral and Lithothamnion. i Spec. 



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