BY THE REV. J. E. TENISON-WOODS. 1063 



Pt. C?) spiracellum, a. Ad. and Reeve ; Pfr. Mon. Pneumon. 

 p. 50= Cyclostoma spiracellum, A. Ad. and Reeve, Voy. Samar. 

 Moll. p. 56, pi. 14, fig. 1 ; Pfr. Mon. Pneumon. p. 50. 



Borneo. 



Pt. labuanensis, Pfr. Proc. Zool. Soc. 1863; Mon. Pneumon. 

 Suppl. 11. p. 41. 

 Labuan. 



Pt. lowianus, Pfr. Proc. Zool. Soc. 1863 ; Mon. Pneumon. 

 Suppl. II. p. 41. 

 Labuan. 



Pt. sumatranus, von Mai't. Monatsber. Berl. Ak. 25 Feb. 

 1864; Pfr. Mon. Pneumon. Suppl. II. p. 42. 

 Sumatra. 



Pt. batchianensis, Reeve, Conch. Icon. sp. 6, pi. 2 ; Pfr. Mon. 

 Pneumon. Suppl. II. p. 43. 

 Batchian. 



Pt. C?) eudaedaleus, Crosse, Jour. Conch. XVII. 1869, p. 187; 

 Pfr. Mon. Pneumon. Suppl. III. p. 51. 

 Borneo, 



24. Spiraculum, Pearson, 1833, Jour. R. As. Soc. II. p. 391 ; 

 H. and A. Adams, Genera, p. 278. 



SJiell depressed, sub-discoid, with a thick periostraca, which is 

 sometimes covered with small hairs ; aperture circular ; at the 

 last whorl a sutural tube formed by the union of the outer layer 

 of the shell over the channel on the penultimate whorl. By most 

 authors this is regarded as a sub-genus of Pterocyclos. 



Spiraculum (J) regelspergeri, de Morgan, Le Naturaliste, 

 VII. 1885, No. 9, p. 69 {Cyclophorus) ; 0. von Mollendorff, Jour. 

 As. Soc. Beng. LV. 1886, p. 308. 



The last-named author says (I.e.) that the species is decidedly 

 not a Gyclophorus but a Pterocyclos, which might be related to 



