CTRTOCEKATID^. 
281 
1860. Cyrtoceras plebeium, Barrande^ Bull. Soc. Geol. de France, 2® s^r. 
vol. xvii. p. 625. 
1867. Cyrtoceras pleheium, Barrande, Syst. Sil. de la Boheme, vol. ii. 
pt. i. p. 525, pi. cix. ff. 11-16, ?pl. civil, ff. 44-46, pi. ccvii. ff. 1-5, 
pi. ccviii. ff. 10-16. 
1882. Cyrtoceras pleheium, Blake, British Foss. Ceph. pt. i. p. 176, 
pi. xix. f. 5. 
8p. Char. Shell strongly and uniformly curved. Upon a chord 
of 50 millim., subtending the concave side of an incomplete specimen, 
the highest perpendicular is 14 millim. The section is oval, the ratio 
of the ventro-dorsal to the transverse axis being as 8 : 7. The body- 
chamber is a little longer than its basal diameter, and occupies about 
-i- of the total length of the shell. The septa have a slight curva- 
ture forwards on the convex border ; they are distant from each 
other ^ the diameter of the shell. There are from 40 to 45 septa 
in the adult shell. The siphuncle is placed upon the convex border, 
without touching the test; it is about diameter of the shell. 
The test has nothing upon it but irregular lines of growth. 
RemarTcs. The species nearest to this one appears to be M. fame- 
licum, Barr. (pi. ccvii.), but it has a proportionately longer body- 
chamber, and it is a stouter and more cylindrical shell. Barrande 
remarks upon the close resemblance between the present species 
and “ Cyrtoceras corniculum, Hall, of the second fauna in America ” 
(Eep. Geol. Surv. Wisconsin, 1862, vol. i. p. 41, figs. 1-2). 
M. pleheium is identified by Prof. Blake from the Wenlock Lime- 
stone in this country. He says : — “ Some little specimens, flattened 
in the Wenlock Limestone, agree, so far as their characters are pre- 
served, with this species ” {loc. cit.). He regards M. maerum, Blake, 
as its nearest ally in the British rocks. 
Horizon, Etage E, bande e 2 ( = Salopian). 
Localities. British. Dudley, Worcestershire (Wenlock Limestone). 
Foreign. Dlauha Hora, Butowitz, Wiskocilka, Bohemia. 
AVell represented in the Collection, which contains the specimen 
figured by Blake. 
Cyrtoceras (Meloceras) problematicum, Barrande, sp. 
1848. Cyrtoceras problematicum, Barrande, Haidinger, Bericht fiber die 
Mittheil. von Freund, der Naturwiss. in Wien, Band iv. p. 209. 
1852. Cyrtoceras problematicum, Giebel, Fauna der Vorwelt, Band iii. 
Abth. i. p. 209. 
1867. Cyrtoceras problematicum, Barrande, Syst. Sil. de la Boheme, 
vol. ii. pt. i. p. 256, pi. cxvi. ff . 1-9, pi. ccvi. ff. 17-25. 
1877. Cyrtoceras problematicum, Barrande, ibid. Suppl. et S6r. tardive, 
p. 172, pi. dvi. ff. 1-6. 
