195 

 4- Rissoina (Phosinella) erythraea Philippi. 



Philippi. Zeitschr. f. Malak. 1851, p. 93. 



Weinkauff. Martini-Chemn. Conch. Cab. Ed. II, Vol. I, Rissoina, p. 39, PI. ir, fig. 6; p. 64, 



PI. 15, fig. 16; PI. 15^, fig. 2 [Seguenziana). 

 Tryon. Man. of Conch. Vol. IX, p. 382, PI. 37, fig. 97—2; PI. 58, fig. 3, 4. 



Stat. 231. Amboina. Reef. 3 Spec. 

 The specimens are rather elongate. 



5. Rissoina (Morchiella) spirata Sowerby. 



SOWERBY. Gen. of Shells. N" 40, PL 208, fig 2. 



Reeve. Conch. Ic. Vol. XX, Rissoa, fig. 17. 



Weinkauff. Martini-Chemn. Conch. Cab. Ed. II, Vol. I, Rissoina, p. 42, PI. 12, fig. 4. 



Tryon. Man. of Conch. Vol. IX, p. 388, PL 58, fig. 29. 



Stat. 66. Bank between islands of Bahuluwang and Tambolungan. 8 — 10 M. Dead coral, 

 Halimeda and Lithothamnion. i Spec. 



This specimen is sufficiently typical. 



mut. deformis Sowerby. 



Reeve. Conch. Ic. Vol. XX, Rissoa, fig. 63. 



Tryon. Man. of Conch. Vol. IX, p. 3S8, PL 59, fig. 35. 



Stat. 125. Sawan, Siau-island. 27 M. Stone and some Lithothamnion. i Spec. 



The only specimen shows more affinity to the next variety than to the type, being more 

 slender and delicate. 



var. Montrouzieri Souverbie. 



Souverbie. Journ. de Conch. 1862, p. 237, PL 9, fig. 5. 



Weinkauff. Martini-Chemn. Conch. Cab. Ed. II, Vol. I, Rissoina, p. 57, PL 14, fig. 15. 



Stat. 19. Bay of Labuan Tring, West coast of Lombok. 18 — 27 M. River-mud, coral, coral- 

 sand. I Spec. 

 Stat. 47. Bay of Bima, near South fort. 55 M. Mud with patches of fine coralsand. i Spec. 

 Stat. 142. Laiwui, North coast of Obi major. 23 M. Mud. I Spec. 



The specimens sufficiently agree with the original figure; it is often difficult with so variable 

 a species, to identify every specimen and to bring it to some described form. It is however still 

 more difficult to keep them separate as good species, unless one destroys intermediate specimens. 



6. Rissoina (Zebina) tridentata Michaud. 



MiCHAUD. Descript. Genre Rissoa, p. 6, fig. 5, 6. 

 Schwarz. v. Mohrenstern. Rissoina, p. 107, PL 9, fig. 74. 



Stat. 78. Lumu-Lumu-shoal. Borneo-bank. Reef, i Spec. 



The specimen is not in very good condition, so I had, like some of my predecessors, 

 first taken it for an Etilima. 



87 



