12 
NAITTrLOIDEA. 
Ophidioceras simplex, Barrande. 
1867. Ophidioceras {Lit.) simplex^ Barrande, Syst. Sil. de la Boheme, 
vol. ii. pt. i. p. 184, pi. xcvii. ff. 1-12. 
1877. Ophidioceras simplex, Barrande, ibid., Supplem. et Serie tardive, 
pi. cccclxxviii. Case i. 
8p. Char. The “ crosse ” or straight part of the shell is verj’ short, 
scarcely | an inch in length. The maximum number of whorls is 
three, both in large and in small examples ; they are just in contact, 
the external being slightly marked by the internal whorls. There 
is a small vacuity in the centre. The transverse section is subtri- 
angnlar. A very distinct flattened keel or band runs along the 
periphery. The body-chamber, including the straight part of the 
shell, occupies about half of the first volution ; its aperture is much 
contracted, and three tongue-like lobes are formed thereby, oue of 
which is a little longer than the other two, the whole forming a 
Y-shaped aperture. The longer of the three lobes corresponds with 
the ventral keel, which, in fact, results from the filling up of the 
extremity of this lobe, very much in the same way that the band in 
Pleurotomaria represents the “ notch ” in its aperture. 
The septa are numerous and but slightly concave ; they are not 
more than half a line distant from each other. The siphuncle is 
placed at a distance of about half a line from the convex or ventral 
border of the shell ; its elements are cylindrical. The surface is 
ornamented with prominent, acute annnlations, which strongly mark 
the cast; they are distant about 1| lines measured from the summit 
of one ridge to that of the neighbouring one, the distance varying a 
little with the age of the individual. The annulations become 
somewhat -weaker as they approach the ventral keel ; each one cor- 
responds with a septal chamber, so that there is always a rib between 
two sutures. The latter, however, are slightly oblique to the annu- 
lations. The test is covered with very fine transverse lines, 3 to 4 in 
the spaces between the ribs, the summits of the latter being smooth. 
Remarl's. The following species, though e-vidently allied to the 
present one, diflPer in the following particulars : — Ophicl. rudens (infra) 
by the possession of 5, instead of 3 whorls ; 0. tesseUatum (infra) 
by the ornaments of the test. 
Horizon. Etage E, bandes e 1 and 2 ( = Salopian). 
Localities. Earlstein, Blauha Hora, Lochkow ; Bohemia. 
Well represented in the Collection. 
