30 
NATTTILOIDEA. 
I have adopted the latter, as I think that the balance of evidence 
is strongly in favour of this species belonging to the genus Trocho- 
eeras, and that its alliances are with such species as T. speciosum, 
Barr., T. tortuosum, Sow., &c. 
Horizon. Lower Ludlow. 
Locality. Parkes Hall, near Dudley (?). 
Represented in the Collection by a single very imperfect example. 
Trochoceras Sandbergeri, Barrande. 
1848. Trochoceras Sandhergeri, Barrande, in Haidinger s Berichte iiber 
die Mittlieil. von Freund, der Xaturwiss. in AVien, Band iv. p. 208. 
1867. Trochoceras Sandhergeri, Barrande, Syst. Sil. de la Boheme, 
vol. ii. pt. i. p. 114, pi. xviii. ff. 7-12, pi. xxix. ff. 1-9. 
? 1867. Trochoceras trochoides, Barrande, ibid. p. 116, pi. xxix. if. 16-26. 
Sp. Char. Shell having a little more than two whorls, increasing 
its diameter about three times for each volution. The transverse 
section is subquadrangular near the aperture, the external border 
being the broadest. The ventro-dorsal diameter of the body- 
chamber is to the transverse as 5 : 4. The body-chamber projects 
from the coiled part of the shell for a distance of about ^ of its own 
length in a nearly straight direction. There is a very perceptible 
constriction near the aperture, which is quite distinct even upon 
the cast. The septa are moderately distant from each other, i. e. 
4 of the shell-diameter. The siphuncle is situated about midway 
between the centre and the convex border. The ornaments of the 
test consist firstly of prominent transverse annulations, which are 
not so conspicuous upon the body-chamber as upon the septate part 
of the shell ; they run backwards with a very considerable obliquity, 
and form a shallow sinus along the convex border. The finer orna- 
ments consist of a network of raised thread-like lines, of which the 
most prominent are the longitudinal ones, and they are also much 
wider apart than the others, which they cross. 
RemarTcs. Trochoceras pulchrum, Barr. (pi. xxviii.), is a nearly 
related form, but the whorls increase more rapidly than those of 
the present species, and the ribs are more numerous.. T. trochoides, 
Barr. (pi. xxix.), is coarser in its form and sculpture than the 
species under description. 
Horizon. Etage E ( = Salopian). 
Locality. Dlauha Hora, Bohemia. 
Well represented in the CoUection. 
