22 
naxjtiloidea. 
approximate ; a little more than 3 lines distant at a diameter of 
1 inch. Bodj-chamber unknown. Siphuncle central. Surface of 
test quite smooth, or with very faint horizontal lines. 
RemarJes. Eeference is made in the synonymy of this and of 
other species occurring in the same beds to the figures given by M. 
E. Bayle, in the Atlas to the ‘ Carte Geologique de la Prance.' 
In order to ascertain if any explanation of this Atlas of Plates 
was likely to be published I wrote to M. Bouville, Engineer-in- 
Chief of Mines, of the “ Ecole des Mines,” Paris, and he very courte- 
ously replied to me to the following efi’ect : that the text which 
should accompany the Atlas had not been begun, and that it was 
not probable that it ever would be completed and published. 
Nevertheless I thought it might be useful to refer to such of M. 
Bayle’s figures as appeared to represent species from the same 
locality contained in the National Collection. 
Horizon. Calcaires ampeliteux ( = Third Fauna of Barrande). 
Locality. Saint-Sauveur-le-Yicomte (Manche), France. 
Well represented in the Collection. 
Orthoceras hastile, Barrande. 
1868. Orthoceras hastile, Barrande, Syst. Sil. de la Boheme, vol. ii. 
Texte iii. 1874 (jauvier), p. 636, pi. cccxxxii. ff. 1-3, pi. ccccxliv. 
ff. 8-10. 
1870. Orthoceras hastile, Barrande, Distrih. des Ceph. dans les 
Contrees Siluriennes, p. 50 (Extrait du Syst. Sil. de la Boheme, 
vol. ii. 4me ser.). 
1876. Orthoceras hastile, Tromelin and Lehesconte, Assoc. Fran^. pour 
I’avancement des Sciences, 4me Sess. (Nantes), p. 621, and 
Tableau D. no. 28. 
Sjp. Char. Section circular. Bate of increase almost imper- 
ceptible. Barrande gives the apical angle as varying between 1° 
and 2°, and concludes that the shell must have attained a great 
length. Very little is known about the septa, but one seen 
below the body-chamber, in a specimen figured by Barrande, has a 
height which represents about | the diameter. The body-chamber 
is imperfectly known. The siphuncle is central, and was probably 
cylindrical. Surface of the test with obscure lines of growth. 
Horizon. Calcaires ampeliteux ( = Third Fauna of Barrande). 
Locality. Saint-Sauveur-le-Vicomte (Manche), France. 
Represented by a large fragment. 
Orthoceras Vibrayei, Barrande. 
1866. Orthoceras Vibrayei, Barrande, Syst. Sil. de la Boheme, vol. ii. 
Texte iii. 1874 (janvier), p. 562, pi. ccx. if. 1-3, pi. ccxiv. ff. 1-3, 
pi. ccclxxxiii. ff'. 1-4, pi. ccccl. if. 4, 5. 
