124 
NAUTILOIDEA. 
close-set annulations and strong longitudinal lines characterizing the 
adult shell. (See Barrande, Syst. Sil. de la Boheme, 1868, pi. ccLxxxvi. 
ff. 14, 16.) 
We have seen also in Orthoceras teres that the surface of the shell 
at its commencement is quite smooth ; and it is not improhahle that 
could we find the early stage of other species they would present a 
similar rudimentary condition of their ornamentation. 
Horizon. Lower Limestone Group’. 
Localities. Boghead, Lanarkshire ; Todmorden, Yorkshire. 
Well represented in the Collection. 
Orthoceras scalare^ d’Archiac & de Verneuil. 
1831. Orthoceratites striolatus, H. v. Meyer, Nova Acta Leop.-Carolin. 
vol. XV. pt. ii. p. 77, Taf. Iv. fi‘. 1, 2 (non Taf. Ivi.). 
1842. Orthoceratites scalaris (Goldfuss, Bonn Museum), d’Archiac & de 
Verneuil, Trans. Geol. Soc. 2nd ser. vol. vi. p. 345. 
1852. Orthoceratites scalaris, Giebel, Fauna der Vorwelt, p. 267. 
1854. Orthoceras scalare, F. A. Roemer, Palseontographica, Band iii. 
p. 49. 
1856. Orthoceras scalare, G. & F. Sandberger, Die Verstein. Nassau, 
p. 167, Taf. xxix. fi*. 5, 5a. 
1882. Orthoceras scalare, Kayser, Beitr. z. Kenntn. von Oberdevon und 
Culm amNordrande des rheinisch. Schiefergebirges, in Jahrh. der 
konigl. preuss. geolog. Landesanst. und Bergakad. zu Berhn fiir 
das Jahr 1881, p. 75. 
1884. Orthoceras scalare, H. Woodward, Geol. Mag. new ser. dec. iii. 
vol. i. p. 538. 
Sjp. Char. Shell straight, very rapidly tapering at the rate of 
about 1 in 3. Section apparently elliptical, but the shell is always 
crushed, so that its form cannot be aeciu’ately made out. The 
siphuncle is unknown. The surface ornaments consist of direct, 
transverse, acute annulations, somewhat irregularly spaced, but 
about 2 lines apart in a diameter of inch. Their breadth 
equals about half the nearly smooth space between them; the latter 
is covered with extremely fine transverse lines, which are seldom 
preserved. They are well figured by the Brothers Sandberger {1. c.). 
RemarTcs. This rare shell is always found in a crushed and dis- 
torted condition, and very seldom has any of its test preserved, a 
hollow space representing it being generally found between the cast 
and the matrix. The septa were probably very thin and fragile, so 
that they could not have given much support to the test after the 
death of the animal ; hence the collapsed condition of the fossils. 
Carboniferous Limestone Series (see footnote, p. 121). 
