20 
THE VOYAGE OF H.M.S. CHALLENGER. 
Genus Firoloida, Lesueur. 
1817. Firoloida, Lesueur, Journ. Acad. Nat. Sci. Philad., vol. i. p. 38. 
1817. „ id., Bull. Soc. Philom. Paris, p. 159. 
1818. Firoloides, Oken, Isis, p. 1557. 
1820. Firoloida, Blainville, Diet. d. Sci. Nat., voL xvii. p. 67. 
1824. Firoloide, id., op. cit., vol. xxxii. p. 283. 
1830. Firoloides, Deshayes, Ency. Meth., vol. ii. p. 130. 
1830. Cerophora, d’Orbigny, Voy. Amir, merid., vol. v. p. 151. 
1841. ,, id., in Sagra’s Hist. Cuba, Moll., vol. i. p. 97. 
1842. „ id., Paleont. frang., Terr, cret., vol. ii. p. 18. 
1850. „ Gray, Fig. Moll. Anim., vol. iv. p. 100. 
1852. Firoloida, Souleyet, Yoy. “Bonite,” Zool., vol. ii. p. 339. 
1853. Firoloides, Leuckart, Wiegmann’s Archiv f. Naturgesch., p. 253. 
1853. Ceratophora, Philippi, Handbuch Conch., p. 283. 
1854. Firoloides, Leuckart, Zool. Untersuch., Heft. iii. pp. 3-68. 
1854. „ Woodward, Man. Moll., p. 199. 
1855. Firolella, Troschel, Wiegmann’s Archiv f. Naturgesch., p. 301. 
1855. Firoloides, Gegenbaur, Untersuch. Pterop. und Heterop., p. 215. 
1855. Firoloidea, H. and A. Adams, Gen. Moll., voL ii. p. 95. 
1856. Firoloides, Troschel, Gebiss d. Schneck., vol. i. p. 45. 
1856. Firolella, id., loc. cit., p. 46. 
1856. Firoloides, Krohn, Muller’s Archiv f. Anat. Physiol., p. 520. 
1857. Firoloida, Gray, Syst. Arrang. Moll., p. 132. 
1857. Cerophora, id., loc. cit., p. 132. 
1859. „ Chenu, Man. Conch., vol. i. p. 124. 
1860. Firoloides, Krohn, Beitrage Entwick. Pterop. und Heterop., p. 27. 
1862. „ Macdonald, Trans. Roy. Soc. Edin., vol. xxiii. p. 5. 
1866. Firoloidea, Keferstein, Bronn’s Thierreich, vol. iii. pt. 2, p. 850. 
1876. Firoloides, Fol, Arch. d. Zool. Exper., vol. v. p. 103. 
1883. „ Tryon, Struct. Syst. Conch., p. 349. 
1883. i firoloida, l Fischer, Man. Conch., p. 580. 
( Cerophora, j ’ 1 
There seems to be considerable diversity of opinion with regard to the value of the 
three so-called genera which I have united under Firoloida of Lesueur. 
This genus was founded for a group of Heteropods which differed from Pterotrachea, 
to which they evidently were closely related, in having the visceral nucleus situated at 
the posterior end of the body, and scarcely any caudal prolongation beyond the nucleus. 
Lesueur also thought that the absence of a fin-sucker and of tentacles were essential 
features of his genus, but this has since been proved not to be the case. 
Two of the specimens figured by Lesueur were females, as is shown by the egg-tube 
being represented in both of his illustrations. Neither of these has tentacles in front of 
the eyes. His third figure represents an animal ( Firoloida aculeata) with two “ elongate 
gelatinous points ” in front and no egg-tube posteriorly. This I am inclined to think was 
a mutilated male in which the genital organ has been broken away, and the two “ elongate 
