64 
NATJTILOIDEA. 
wider apart, and the aimulations are less salient than they are in 
0. pulchrum and they also become obsolete towards the aperture. 
All these species are remarkable for the singular beauty of their 
ornamentation, which is, however, parallelled by that of other species 
in the Devonian rocks above them, to some of which they are closely 
related h 
Horizon. Etage E, bande /2 ( = Downtonian). 
Locality. Konieprus, Bohemia. 
Eepresented by two examples. 
Orthoceras Hisingeri, Boll. 
1831. Orthoceratites annulatus, Hisinger, Anteckn. i Physik och 
Geognosie, Haftet 5, p. 112, tab. iv. f. 5. 
1837. Orthoceratites annulatus, Hisinger, Lethtea Svecica, p. 29, 
tab. ix. £ 8. [Not Orthoceras annulatum, Sow.] 
1857. Orthoceras Jlisingeri, Boll, Archiv des Ver. der Freuude der 
Natiirg. in Mecklenburg, .Jalirg. xi. p. 18, Taf. v. f. 13. 
1857. Orthoceras Gottlandicum, Boll, ibid. p. 19, Taf. v. f. 14. 
1870. Orthoceras Hismyeri, Barrande, Syst. Sil. de la Boheme, vol. ii. 
Texte iii. 1874 (Janvier), p. 700, pi. ccccxli. ff, 17-19. 
\_Not 1851. Orthoceras Hisinyeri, Marie Rouault, Bull. Soc. Gdol. de 
France, ser. 2, tom. viii. p. 360. — 1870. Orthoceras Gothlandicum ?, 
Barrande, loc. cit. p. 699, pi. ccccxli. AT. 14-16 (not f. 13).] 
Sp. Char. Shell straight. Section circular. Rate of increase 
very slow, about 1 in 23. Body-chamber very long, more than 4 
times the diameter of the base. Septa at frequent inteiwals ; 
distant about the diameter. Siphuncle central. Surface with 
very strong subangular aimulations, situated midway between the 
septa, and divided by concave interspaces. The annulations are as 
strong upon the cast of the shell as they are upon the testaceous 
portions. The surface of the test is covered with fine, transverse 
crenulated striae, about 18 or 20 of which occupy 1 line ; they are 
more crowded upon the ribs than between them. 
RemarTcs. The afiinities subsisting between this species and 0. 
dulce, Barr., have already been pointed out. It is sufficiently dis- 
tinguished from 0. ibex by the sculpture of its test. 
I am indebted once more to the kindness of Dr. Lindstrom in 
supplying me with some valuable notes on the present species. In 
sending me a little sketch of the minute sculpture of the test of 
0. Hisinyeri, he remarks that Barrande’s figures (loc. cit. pi. ccccxli. 
ff. 17-19) represent a specimen “ somewhat deviating from those 
^ Cf. e. g. Orthoceras tenuilineatum, Sandb. Yerstein. Nassau, 1856, p. 168, 
Taf. xix. f. 7. 
