232 
ACTINOPTERYGrII. 
fig. 6. — Kimmeridgian; Chaux-du-Milieu, Neuchatel. 
[Portion of vomer ; Neuchatel Museum.] 
Microdon formosus, J. J. Heckel, Denkschr. k. Akad. Wiss., math.- 
naturw. Cl. vol. xi. (1856), p. 201. Pycnodusformosus, A. 
Wagner, Abh. k. bay. Akad. Wiss., math.-phys. Cl. vol. vi. 
(1851), p. 40, pi. iii. fig. 4.—Lower Kimmeridgian (Diceras- 
kalk) ; Oberau, near Kelheim, Bavaria. [Portion of right 
splenial; Palaeontological Museum, Munich.] 
Microdon irregularis : Pyknodus irregularis , P. A. Quenstedt, Der 
Jura (1858), p. 781, pi. xcvi. fig. 32 b—Upper Corallian; 
Schnaitheim, Wiirtemberg. [Portion of vomer; Tiibingen 
University Museum.] 
Microdon (?) minor ; Pycnodus minor , P. A. Poemer, Yerstein. 
Norddeutsch. Oolithengeb., Nachtr. (1839), p. 54.— 
Portlandian ; Galgenberg, near Uildesheim, Hanover. 
[Splenial.] 
Microdon vicinus : Pycnodus vicinus, J. Cornuel, Bull. Soc. Geol. 
Prance, [3] vol. xi. (1883), p. 20, pi. i. figs. 8, 9.—Port¬ 
landian ; Yille-sur-Saulx, Meuse. [Splenial.] 
An undefined species of Microdon is also indicated -by imperfect» 
jaws from the Lower Kimmeridgian of Orbagnoux, Ain, France 
{Pycnodus sp., H. E. Sauvage, Bull. Soc. Hist. Nat. Autun, vol. vi. 
1893, p. 443, pi. ix. fig. 2). 
The genus has been erroneously recorded from the Cretaceous. 
The so-called Microdon nuchalis (P. Dixon, Geol. Sussex, 1850, 
p. 369, pi. xxxii. fig. 7) is founded upon an imperfect example of a 
teleostean fish from the Chalk of Sussex, now in the British Museum 
(Platax ? nuchalis, A. S. Woodward, Ann. Mag. Nat. Hist. [5] 
vol. xx. 1887, p. 342). Microdon occipitalis (P. Dixon, op. cit. 
p. 369, pi. xxxii*. fig. 2) is a name given to a generically indeter¬ 
minable fragment of a Pycnodont from the Chalk of Lewes, in the 
Brighton Museum. 
Microdon ? pidchellus (J. W. Davis, Trans. Boy. Dublin Soc. [2] 
vol. iii. 1887, p. 501, pi. xxiv. fig. 3), from the Upper Cretaceous of 
Sahel Alma, Mt. Lebanon, is a teleostean fish. The type specimen 
is now in the Edinburgh Museum. 
An indeterminable fossil from the Cretaceous of Pietraroja, Naples, 
is named Microdon simplex , O. G. Costa, Atti Accad. Pontan. 
vol. viii. (1864), p. 112, pi. ix. fig. 7. JJhM-fvy? - S**-* / - (/f S?)p>. i 
1 An Eocene fossil from Bavaria, certainly not of this species is recorded 
under the same name by K. Schafhautl, Siid-Bayerns Leth. Geogn. (1863), p. 246 
pi. Ixv. c. fig. 16. 
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