530 THE VOYAGE OF H.M.S. CHALLENGER. 



straight set on ; it consists of 4^ whorls, the third of which is perceptibly more tumid 

 than the rest ; and the last begins to spread out as a sort of base to the pillar-like style. 

 Whorls 7^, regular, flat-sided, and cylindrical, only at the very top and bottom conical ; 

 the last whorl is slightly, slowly, and conically contracted to the point of the base ; the 

 edge of the lip is very prominent at the side outline, and in front passes beyond the 

 pillar-point. Suture : its position is well defined by the furrow, but itself is quite invisible. 

 Mouth gibbously round, with a small sinus above and a very small but deep canal in front, 

 which twists in towards the back of the pillar, and in front is almost closed by the over- 

 lapping of the lips. Outer lip thin, patulous, concave above, very prominent, and slightly 

 angulated at the corner of the base, a little straight in front ; at the canal the lip-corner 

 runs out into a little point, covering and almost touching the tip of the pillar ; the edge 

 of the canal is slightly reverted. Pillar very short and stumpy. Inner lip pretty 

 thick on the body, with a well-defined edge, especially on the pillar; concave. H. O'll in. 

 B., in the middle, 0-034 ; at the last whorl, 0"032. Mouth, height 0023, breadth 0'018. 

 Apex, height 0-014, breadth 0-009. 



This species in a general way is not unlike some of the dwarf forms of Ccrithiopsis tubercularis 

 (Mont.,) but in details of sculpture, and especially in its singular apex, it is very different. 



Family Cerithiacea, Menke, 1828. 



Genera. 1. Cerithium, Adanson. 2. Bittium, Leach. 3. Triforis, Deshayes. 4. Alaha, H. and A. Adams. 



5. Litiopa, Rang. 6. Planaxis, Lamarck. 



1. Cerithium, Adanson, 1757. 

 Species. 



1. Cerithium balteatum, Phil. 9. Cerithium phoxum, Wats. 



2. Cerithium carbonarium, Phil. 10. Cerithium lissum, Wats. 



3. Cerithium columna, Sow. 11. Cerithium (Lampania) australe, Quoy and Gaim. 



4. Cerithium dubium, Sow. 12. Cerithium (Vertagus) articulatum, Ad. and Rve. 



5. Cerithium novcehollandice, A. Adams. 13. Cerithium (Vertagus) asperum (Linne). 



6. Cerithium salebrosum, Sow. 1 4. Cerithium ( Vertagus) Icoehi, Phil. 



7. Cerithium vulgatum, Brug. 15. Cerithium (Vertagus) martinianum, Pfeiffer. 



8. Cerithium matukense, Wats. 16. Cerithium (Vertagus) turritum, Sow. 



1. Cerithium balteatum, Philippi. 



Cerithium balteatum, Philippi, Abb. und Beseh., vol. iii. p. 16 (bis), pi. xxii. (Gen. i.) fig. 10. 

 „ „ Sowerby, Thes., vol. ii. pt. 16, p. 862, sp. 56, pi. clxxxi. figs. 116, 117. 



„ „ Reeve, Conch. Icon., vol. xv. (1865), pi. xi. fig. 72. 



„ „ Brazier, "Chevert" Exprd MolL, Proe. Linn. Soc. New South Wales, 1877, 



voL i. p. 314, No. 11. 



