II 



'^ Spirialis' retroversiis is coiled to the right, while Boas figured ') that of "" Limacina' reticulata 

 as a right-handed spiral. Pelseneer corrected ') this, but he says about the operculum of 

 Liniacina that it exhibits a right-coiled direction '*). 



In reality the operculum of Peraclis is left-coiled, as it has been represented by d'Orbigny, 

 long before Souleyet. 



Pelseneer stated ^) afterwards that the operculum of Limacina retroversa was left-handed, 

 a fact which, after m\- own researches, holds good in the three species of the Siboga-material 

 too. The operculum of Limacina inflata is figured PI. I, fig. i. In the two other species it 

 shows a more elongated shape. 



In Peraclis the operculum e.xhibits the same left-handed direction. 



The beginning of its spiral is turned to the umbilicus (false spira). 



Limacina Cuvier. 



1817. Limacina Cuvier, Le Regne animal, t. II, p. 380. 



1823. Hetcrofusus Fleming, On a reversed species of Fusiis, Mem. Wern. Soc, p. 498. 



1824. Spiratdla de Blainville, Diet. d. Sci. Nat., t. XXXII, p. 284. 



1836. Heliconoides (part.) d'Orbigny, Voyage d. I'Amer. mer., t. V, p. 174. 



1840. Spirialis (part.) Eydoux et Souleyet, in: Revue Zool., t. Ill, p. 235. 



1842. Helicophora Gray, Synopsis of the contents of the British Museum, p. 59. 



1844. Scaea Philippi, Fauna Molluscorum utriusque Siciliae, p. 164. 



1 86 1. Protomedea (part.) Costa, Microdoride mediterranea, p. "jt,. 



1869. Embolus Jeffreys, British conchology, vol. V, p. 114. 

 1885. Limacina (part.) Boas, SpoHa atlantica, p. 39. 



I. Liviacina inflata (d'Orbigny). 



1836. Atlanta inflata d'Orbigny, Voyage dans I'Amerique meridionale, vol. V, p. 174, pi. 12, 



figs. 16 — 19. 

 1840. Spirialis rostralis Eydoux et Souleyet, Description sommaire de plusieurs Pteropodes 



nouveaux ou imparfaitement connus. Revue Zoologique, vol. 3, p. 236. 

 1850. Limacina inflata Gray, Catalogue of the Mollusca in the collection of the British Mus., 



Prt. II, Pteropoda p. 31. 

 1852. Limacina scaphoidea Gould, The Mollusca and Shells of the U.S. Exploring Expedition, 



p. 485, pi. 51, fig. 602. 

 1861. Protomedea elata O. G. Costa, Microdoride mediterranea, p. 74, pi. 11. fig. 5. 



1870. Embolus rostralis Jeffreys, Mediterranean Mollusca, Ann. and Mag. Nat. Hist., ser. 4, 



vol. 6, p. 86. 

 1882. Protomedea rostralis Fischer, Sur le faune Malacologique abyssale de la mediterranee, 



Comptes rendus, vol. XCIV, p. 120. 

 1889. Embolus inflatus Dall, in: Bullet. U. S. Nat. Mus., n" n, p. 80. 



Living animals: 



Stat. 35. 8° o'.3 S., 1 16° 59' E. i spec. 



Stat. 66. Between Bahuluwang a. Tambolungan, south of Saleyer. 2 spec. 



Stat. 95. 5°43'.5N., ii9°4o'E. Sulu Archipelago. 2 spec. 



i) Spolia atlantica, pi. Ill, fig. Sg/'/V. 



2) Chall. Rep. LXV, p. 33. 



3) Ibid., p. 16. 



4) Sur la dextvoisite de certains Gastropodes dits "senestres". Comptes rendus, 1891, t. CXll, p. 1016. 



