66 
NAUTILOIDEV. 
Orthoceras ornatum, Boll. 
1857. Orthoceras ornatum, Boll, Arcliiv fiir ^leckleiibiirg, xi. Jahrg. 
p. 20, Taf. V. f. 16, a, b. 
1869. Orthoceras ornatum, Heidenliain, Ueber Graptolithen fiilirende 
Diluvial-Gescbiebe der norddeutschen Ebeue, p. 24. 
1870. Orthoceras temerum, Ban-ande, S>'st. Sil. de la Bobeme, vol. ii. 
Texte iii. 1874, p. 708, pi. ccccxli. ft. 6-12. 
? 1878. Orthoceras sp. [ornatum ?, BoU], Haupt, Die Fauna des 
Graptolithen-Gesteines, p. 52. 
Sp. Char. Section probably circular, though often appearing 
elliptical by compression. Rate of increase 1 in 13. Length of 
body-chamber not accurately known, but in a fragment it measures 
more than 3 times the diameter of the base. The se[)ta are distant 
about -1- the longer diameter, near the base of the body-chamber. 
The siphuncle appears to be eccentric. The ornaments consist of 
prominent, rounded, transverse undulating annulations, about 2 
lines distant from each other, measured from summit to summit. 
Between and on these there are fine simple striae, 4 or 5 of which 
lie in the spaces between the annulations, and 3 or 4 upon them ; 
all being about equidistant. The striae are slightly undulating, 
following the contour of the ribs. (Fig. 5.) 
BemarTcs. This species differs from 0. annulatum, Sow., and its 
varieties, to which it is doubtless closely allied, by the closer 
proximity of its annulations, the absence of longitudinal elevations, 
and the greater width separating the striae, and also by the absence 
of crenulations in the latter. 
Horizon. Upper Ludlow. 
Locality. Island of Gothland, Sweden. 
Well represented in the Collection by a series of specimens pre- 
sented by A. H. Foord. 
Orthoceras virgatum, Sowerby. 
1839. Orthoceras virgatum, Sowerby, in Murchison’s Sil. Syst. p. 620, 
pi. ix. f. 4. 
1852. Orthoceras angulatum, M‘Coy, British Pal. Foss. lasc. ii. 
p. 313. 
1854. Orthoceras angulatum, Salter, in Murchison’s Siluria, pi. xxviii. 
f. 4. 
? 1854. Orthoceras angulatum, Morris, Cat. British Foss. 2nd ed. 
p. 309. 
1882. Orthoceras angulatum, Blake, British Foss. Ceph. pt. i. p. 106, 
pi. vii. ff. 1, 3, 3«. {Not ff. 4, 8, 9.) 
[Aoif 1852. Orthoc. virgatum?. Hall, Pal. of New York, vol. ii. 
p. 219, pi. Ixiii. ff. 2, 3.] 
