The Protoconch of Orthoceras. — Clarke. 113 
striction, or otherwise distinguished from the other septa of 
the shell. 
This "Anfangskammer" of Braneo is considered by Hyatt as 
likewise the first chamber, but of a secondary condition of 
growth, and not as the embryonal shell; while the "Narhe" or 
cicatrix is regarded as the remnant of the protoconch. In 
Professor Fh'atfs earlier papers this interpretation of the 
cicatrix was largely a matter of deduction, for no specimens 
of Orthoceras had then been observed which retained much 
further trace of this feature than a shriveled obsolescent lump 
or scar on the end of the first chamber, but in the progress of 
his investigation material has been brought to light which 
places beyond a doubt the correctness of his interpretation. 
He has confirmed the point in his recent masterly essay on the 
"Genesis of the Arietidae," and illustrated it with original fig- 
ures of Orthoceras politum, Klipstein, and 0. elegans, Muenster, 
from the St. Cassian beds.* 
The protoconch of these species, though conspicuous in 
comparison to its usual condition of retention, is still but a 
shrunken, wart-like appendix, its size being in strong contrast 
to that of the first chamber. 
Hyatt explains the wrinkled aspect of this lump by "assum- 
ing it to have been composed of conchiolin. This accounts 
for its almost invariable absence, since such an organ must 
have been easily lost or destroyed. The lumps must conse- 
quently be regarded as the remnants of conchiolinous proto- 
conchs having elongated and narrow apertures; but probably 
they were, when in a living condition, much larger and more 
oval and more similar to the protoconch of the Ammonoids."+ 
The purpose of this note is to describe and illustrate a pro- 
toconch evidently of a species of Orthoceras, found in the 
Styliola tiniest one of the Genesee shales, on ( ianandaigua Lake. 
N. Y., in an asssociation of species which represents the ear- 
liest appearance in this country of the fauna of Goniatites in- 
tumescens, Bey rich. J 
1 
*Op. cit., page 10. 
tOp. cit., page 9. 
JFor a preliminary list of the species of this fauna, both in its first ap- 
pearance in the Styliola limestone and in its reappearance and more 
abundant development in the Naples beds, see Neues Jahrbuch fur 
Mineralogie, etc., vol. i, p. 161, 1891, and American Geologist, p. 86, 1891. 
