ENDOCERATLD^. 
153 
casts of the siphuncular sheaths and the long slender tube in figure 
la, which extends from the broken sheath, is evidently the endosi- 
phon. E. gJadins has a wide geographical distribution, being found 
in Esthonia, Sweden, and Norway. It may be distinguished from 
E. Wahlenhergi by the great size of its siphuncle and distant septa. 
Horizon. Or^^ocm/s-Limestone (=Arenig). 
Locality. Island of Oeland, Sweden. 
The Collection contains one example presented by A. H. Eoord. 
Endoceras proteiforme, Hall. 
1847. Endoceras proteiforme, Hall, Pal. of New York, vol. i. p. 208, 
pi. xlviii., pi. xlix,, pi. 1., pi. liii. f. 2. 
1852. Endoceras proteiforme, Shmnard, in D. H. Owen’s Geol. Surv. of 
Wisconsin, Iowa, and Minnesota, p. 626. 
1863. Orthoceras proteiforme, Billings, Geol. of Canada, Appendix, 
p. 950. 
1875. Orthoceras proteiforme, Chapman, Outlines of the Geol. of 
Canada, Introd. p. xxiv, pi. iii. f. 37. 
iip. Char. “ General form cylindrico-conical, more or less 
elongated, often compressed, tapering somewhat unequally in different 
specimens ; . . . surface marked by distinct transverse striae, 
which usually appear like narrow subimbricating bands, with one 
edge well defined and more elevated than the other, more or less 
distinctly striated longitudinally ; striae varying from extreme 
tenuity to distinct elevated thread-like lines ; section circular ; septa 
distant from one fifth to one fourth the diameter ; siphuncle excen- 
tric or submarginal.” {Hall.) 
liemarlcs. A specimen in the Collection which may belong to this 
species exhibits traces of the septa externally, but the latter have 
been completely destroyed internally, and the cavity so produced is 
partly occupied by a smaller Orthoceratite in which one or two septa 
are preserved, the rest of the shell being filled with calc-spar, which 
has obliterated most of the septa, as well as the siphuncle. 
Horizon. Trenton Formation ( = Bala Limestone group). 
Locality. Trenton Falls, New York State. 
Represented in the Collection by two specimens. 
[Endoceras proteiforme, Hall, var. tenuistriatum, Hall, and var. 
tenuitextum, Hall, Pal. of New York, 1847, vol. i. pp. 209, 210. 
The Collection contains some specimens which evidently agree with 
these forms, but it appears to me that the evidence is wanting to 
show that they belong to the genus Endoceras. 
^ German “ Spiess French “broche.” 
