178 MOLLUSCA. 
Doubtful Species of Labyrinthus. 
As there is some uncertainty regarding L. hydeanus and L. otis (labyrinthus), both 
of which have often been confounded with ZL. plicatus, and as one of them has been 
quoted from Panama and the other from Central America, it is advisable to add here 
the synonymy of these two species. 
Labyrinthus hydeanus. 
, Knorr, Vergniig. der Augen, v. p. 42, t. 26. fig. 5 - 
Helix labyrinthus (Chemn.), Lamarck, Journ. d’Hist. nat. de Paris, ii. p. 352, t. 42. fig. 4 (1792) *. 
Helix labyrinthus (part.), Férussac, Hist. Nat. Moll. Terr. et Fluv. t. 154 8. fig. 4°. 
Carocolla labyrinthus, Reeve, Conch. Syst. ii. p. 73, t. 167. fig. 3 - 
Carocolla hydeana, Lea, Obs. Gen. Unio, ii. p. 74, t. 23. fig. 73 (1836) ’. 
Helix plicata (Born), Pfr. Monogr. Helic. Vivent. i. p. 398° ; in Martini & Chemnitz, Syst. Conch.- 
Cab. ed. 2, Helix, ii. p. 204. no. 662, t. 104. figg. 1-4"; Reeve, Conch. Icon. vil., Helix, 
t. 100. figg. 553 a, b*; v. Mart. in Festschr. d. Ges. naturf. Freunde in Berlin, 1873, 
p. 168°. 
Distinct from L. plicatus only by the internal lobe of the aperture being not so long 
and narrow, and by the exterior basal tooth being much smaller, with a much 
greater interval between itself and the parietal fold. In most specimens this tooth 
is simply triangular, but it occasionally varies: Lea’s figure® shows it slightly 
trilobate. Generally the colour of the shell is of a darker brown and the aperture 
dirty reddish, not white; but specimens of the true L. plicatus are sometimes similarly 
coloured. 
Hab. VenEzveLa: Puerto Cabello (Gibbon®, Appun®); Caracas (Lansberg *). 
Pfeiffer ®7 gives also Panama as a locality; but as he identifies the species with 
L. plicatus and does not name the collector, this statement is scarcely trustworthy. 
Labyrinthus otis. 
, Favanne, in Dezallier d’Argenville’s Conch. ed. 3, t. 63. fig. F 11 (without text) (1780) °. 
Heliz otis, Solander, in Portland’s Cat. p. 38 (without description) terres 17 8) * 
Helix labyrinthus, Chemnitz, Syst. Conch.-Cab. ed. 1, xi. p. 271, t. 208. fig. 2048 ° (copied from 
Favanne), and ed. 2, t. 2. fig. 5*; Pfr. Monogr. Helic. Vivent. i. p. 897°, and in Martini 
& Chemnitz, Syst. Conch.-Cab. ed. 2, Helix, ii. p. 205. no. (84) (excl. varietat.) °. 
Lyrostoma labyrinthus, Swainson, Malacol. p. 329". 
Hab. 
t Pfeiffer gives °° generally “ Central America.” 
It is possible that Favanne’s figure is very incorrectly drawn, and that J. otvs is 
simply identical with LZ. plicatus (Born), as the species has not again been found ; 
