1 1 



Both specimens are young and rather worn, this last perhaps on account of the marine 

 locality, the dead shells probably having been washed from a brook, or river to the sea. They 

 agree sufficiently with a specimen from Celebes in my possession. One of the specimens (the 

 other being broken) ancl that from Celebes, have a very small tubercle near the base of the 

 pillar-edge, though v. Martens says (1. c. p. 69) "ohne Leiste". 



10. Neritina (Neritodryas) dubia Chemnitz. 



CHEMNITZ. Conch. Cab. V, p. 324, PI. 124, fig. 2019, 2020. 



v. Martens. Martini-Chemn. Conch. Cab. Ed. II, Neritina, p. 136, PI. 12, fig. 1 — 7. 



Stat. 131. Beo, Karakelang-islands; shore. 3 Spec. 



Stat. 200. Rivulet near Bara-bay, North coast of Buru-island. 1 Spec. 



1 1 . Neritina (Neritodryas) subsulcata Sowerby. 



Sowerbv. Conch. Illustr. N° 50. 



V. MARTENS. Martini-Chemn. Conch. Cab. Ed. II, Neritina, p. 142, PI. 12, fig. 11, 12. 



Stat. 131. Beo, Karakelang-islands; shore. 1 Spec. 



Stat. 180. North coast of Pulu-Kelang, small river. 2 Spec. 



One of the specimens from Stat. 1 80 has a yellowish streak near the outer margin of 

 the operculum, this is also the case in a specimen from Ternate. 



12. Neritina (Clithon) brcvispina Lamarck. PI. VIII, fig. 4. 



Lamarck. An. s. vert. Ed. I, Vol. VI, p. 1S5. 



RUMPH. Amb. Rariteitkamer, p. 7S, PI. 22, fig. O. 



v. Martens. Martini-Chemn. Conch. Cab. Ed. II, Neritina, p. 156, PI. 17, fig. 1 — 4, 9. 



Weber, Zool. Ergebn. Band IV, Süss- u. Brackw. Moll. p. 79. 



Stat. Nusa-laut, small river. 1 Spec. 



Stat. 19. Bay of Labuan-Tring, West coast of Lombok, river. 5 Spec. 



Stat. 33. Bay of Pidjot, Lombok, river. 32 Spec. 



The specimens belong to the variety ïnntiea v. Martens, only a few ones from Stat. 33 have 

 one or two very short spines, the colour of the specimens from this locality is very variable. 



According to v. Martens, (Mon. Neritina, p. 158) the radula of this species should be 

 variable; Schacko should have found in spiniferous specimens from Amboina, thé mushroomlike 

 tooth with 24 very sharp denticles, and the uncini with 8 denticles, whereas those from Timor 

 should have those teeth with smooth margins. I have examined the radulae of two specimens 

 from Stat. 33, which agree in nearly every point ; the rhachidian tooth has a larger, nearly 

 square cusp, the first laterals are oblong, with a cusplike margin, the two small laterals are 

 covered by the mushroomlike tooth (PI. VIII, fig. 4), its margin is provided with about 30 small 

 denticles, the uncini have about 10 small teeth on the outer margin. 



*I3. Neritina (Clithon) diadema Recluz. 



Recluz. Revue Zool. 1841, p. 277. 



v. Martens. Martini-Chemn. Conch. Cab. Ed. II, Neritina, p. 154, PI. 15, fig. 22 — 26. 



*Java. 2 Spec. 



11 



